通信方面的英文文獻(xiàn)翻譯?。?
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以下是文獻(xiàn)的一部分，愿意幫忙的高手留下郵箱，我把文件發(fā)給你，若能完成，加分：SpatialCompressiveSensingApproachForFieldDirectionalityEstimation.I.INTRODUCTIONVarietyoft... 以下是文獻(xiàn)的一部分，愿意幫忙的高手留下郵箱，我把文件發(fā)給你，若能完成，加分： Spatial Compressive Sensing Approach For Field Directionality Estimation. I. INTRODUCTION Variety of techniques for field directionality estimation were studied in literature [1]-[5]. Thus， a theoretical analysis of the relationship between the hydrophone array output and the noise field was conducted in [1]-[5]. The developed techniques were based on the array beamformer output or the crossspectral matrix between outputs of array elements [4]-[5]. The problem of a field directionality estimation in ocean， using horizontal line towed array was also addressed in literature [5]- [8]. Recently， problems of direction of arrival and field directionality estimation for moving sensors arrays have attracted renewed interest [9]-[12]. It was shown that an array motion can improve an array performance assuming temporal coherence of successive samples [10]-[11]. In [12]， the wavefield sampling method that exploits the linear relationship between the noise field and the collection of beamformer outputs over various array orientations was proposed. It was shown that the wavefield sampling (WS) method outperforms other tested methods. This algorithm was implemented via the recursive estimation method and its convergence to the unique solution was promised for a specific set of array orientations and beamformer look directions. However， a method for a proper array orientation and beamformer look direction sequence selection remains an open question. The quality of the field directionality estimation is determined by the angular resolution. The higher angular resolution is， the more accurate estimation of the far field sources， and better detection performance can be achieved. One of fundamental relations in the array signal processing is that the angular resolution is directly proportional to the number of the array elements [13]. This relation motivates the desire for longer arrays that can achieve higher resolution. Unfortunately， the requirement contradicts the implementation and installation limitations that motivate shorter arrays. Moreover， implementation of longer arrays for maneuvering platforms such as unmanned underwater vehicles (UUV) can even be impossible [14]. These contradictions motivate the quest for alternative array signal processing methods. Usually， the field directionality is modeled as a finite set of strong far-field narrow-band sources and an isotropic lowpower noise [1]. In this work， the model of the field directionality is adopted in the following way. First， the bearing angle space is uniformly sampled into a large number of discrete angles. Next， it is assumed that ether the high energy that corresponds to the far-field strong sources or the low-energy that corresponds to the isotropic noise is received at the sensor array from every of these discrete azimuth angles. 展開
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- 遙唬掩XJz 2010-01-19 00:00:00
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- 少女情0209 2010-01-19 00:00:00
- 我是樓主 問(wèn)題不知怎么搞的不能補(bǔ)充，我換個(gè)號(hào)來(lái)補(bǔ)充一下： 文件下載地址：http://mail.qq.com/cgi-bin/ftnExs_download?k=5a633438cb20c3cb20365d1e13610a1b0f5b560851550b0714540d08564c0c060155190103575a190a53000850025b0c58070701354e386749024051540d1877560e444a50124b5d4f06146b500f4b5d5704147945114a5b58005c18730e4a1a174d1a68712738&t=exs_ftn_download&code=0efe4abd&s=email&t=exs_ftn_download&code=8391d8ce 提取碼 9c485a84
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- baikaile003 2010-01-18 00:00:00
- 空間遙感方法對(duì)壓場(chǎng) 方向性估計(jì)。 一，導(dǎo)言 為外地的方向性品種的估計(jì)技術(shù) 研究文獻(xiàn)[1] - [5]。因此，理論分析 之間的水聽器陣列輸出的關(guān)系 噪聲場(chǎng)中[1]進(jìn)行 - [5]。發(fā)達(dá)國(guó)家技術(shù) 是基于陣列波束輸出或crossspectral 數(shù)組元素之間的產(chǎn)出[4] - [5矩陣]。那個(gè) 問(wèn)題是在海洋領(lǐng)域的方向性估計(jì)使用， 水平線拖曳陣還討論了文獻(xiàn)[5] - [8]。Z近，到達(dá)方向和領(lǐng)域的方向性問(wèn)題 提出傳感器陣列估計(jì)吸引了 新的興趣[9] - [12]。結(jié)果表明，數(shù)組的議案 數(shù)組可以提高性能假設(shè)時(shí)間相干性 連續(xù)樣本[10] - [11]。在[12]，波場(chǎng) 抽樣方法，利用了線性關(guān)系 現(xiàn)場(chǎng)的噪音和多波束形成產(chǎn)出集合 各陣列方向提出。結(jié)果表明： 波場(chǎng)抽樣（是）方法優(yōu)于其他測(cè)試 方法。該算法通過(guò)實(shí)施遞歸 估算方法及其收斂性的獨(dú)特的解決方案 是許諾的方針和一系列具體規(guī)定 波束研究方向。然而，一個(gè)正確的方法 陣列波束的方向和研究方向序列 選擇仍然是一個(gè)懸而未決的問(wèn)題。 該油田的方向性估計(jì)質(zhì)量是決定 的角分辨率。較高的角分辨率 是，在遠(yuǎn)場(chǎng)的來(lái)源更準(zhǔn)確的估計(jì)， 和更好的檢測(cè)性能可以實(shí)現(xiàn)的。其中 在陣列信號(hào)處理的基本關(guān)系是： 的角分辨率是成正比的數(shù)目 數(shù)組的元素[13]。這種關(guān)系的愿望激勵(lì) 更長(zhǎng)的陣列，可以實(shí)現(xiàn)更高的分辨率。不幸地， 違反規(guī)定的實(shí)施和 安裝限制，激勵(lì)短陣列。而且， 較長(zhǎng)的數(shù)組執(zhí)行機(jī)動(dòng)平臺(tái) 如無(wú)人（無(wú)人潛航器），水下機(jī)器人，甚至可以 不可能的[14]。這些矛盾的追求激勵(lì) 替代陣列信號(hào)處理方法。 通常，外地方向性被建模為有限集合 強(qiáng)遠(yuǎn)場(chǎng)窄帶源和各向同性低功率 噪音[1]。在這項(xiàng)工作中，該字段的方向性模型 采用以下方式。首先，軸承角 空間均勻取樣到大量的離散 角度。其次，假定醚的高能量 對(duì)應(yīng)于遠(yuǎn)場(chǎng)強(qiáng)來(lái)源或低能量 對(duì)應(yīng)于各向同性噪聲的傳感器接收 陣列從這些離散方位角每個(gè)。
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- chang67420433 2010-01-18 00:00:00
- 空間壓縮感應(yīng)法的領(lǐng)域 指向性估計(jì)。 介紹。 各種技術(shù)領(lǐng)域的方向性估計(jì) 在文獻(xiàn)[1]，[5]。因此，進(jìn)行了理論分析 水聽器陣列之間的關(guān)系和輸出 噪聲場(chǎng)進(jìn)行了[1]，[5]。發(fā)達(dá)的技巧 基于陣列輸出或crossspectral聲源定位 陣列天線陣元輸出之間的矩陣，[4]，[5]。這個(gè) 一場(chǎng)的問(wèn)題，利用方向性估計(jì)在海洋中 橫線陣拖也在文獻(xiàn)[5] [8]。Z近，問(wèn)題的波達(dá)方向與領(lǐng)域的方向性 估計(jì)為移動(dòng)傳感器陣列吸引了 新的[9]，[12]。它顯示一個(gè)數(shù)組的運(yùn)動(dòng) 可以改善數(shù)組的一致性假設(shè)顳性能 連續(xù)的樣品[10]-[11]。在[12]，波場(chǎng) 抽樣方法，利用線性關(guān)系 汽車所產(chǎn)生的噪音和收集的聲源定位。輸出 各陣方向。結(jié)果顯示 通過(guò)抽樣的方法優(yōu)于其他(WS)的測(cè)試 方法。該算法通過(guò)遞歸的實(shí)施 估算方法及其收斂的獨(dú)特的解決方案 承諾是為某一特定的數(shù)組取向和嗎 看起來(lái)問(wèn)路。聲源定位然而，對(duì)于一個(gè)適當(dāng)?shù)姆椒? 數(shù)組的定位與聲源定位看起來(lái)方向序列 選擇仍然是個(gè)謎。 這個(gè)領(lǐng)域的質(zhì)量評(píng)價(jià)是確定的方向性 角分辨率的。較高的分辨率 是，更準(zhǔn)確的估計(jì)的遠(yuǎn)場(chǎng)源， 更好的檢測(cè)性能才能得以實(shí)現(xiàn)。之一。 基本關(guān)系中的陣列信號(hào)處理是那個(gè) 角分辨率的數(shù)量成正比 這個(gè)數(shù)組的元素[13]。這種關(guān)系的愿望激勵(lì) 長(zhǎng)陣列，可達(dá)到更高的分辨率。不幸的是， 矛盾的要求執(zhí)行 安裝，激發(fā)短的數(shù)組。另外， 執(zhí)行長(zhǎng)的陣列機(jī)動(dòng)平臺(tái) 如無(wú)人水下車輛(UUV)，甚至可以 可能[14]。這些矛盾，激發(fā)探索 替代陣列信號(hào)處理方法。 通常，磁場(chǎng)定向被視為一個(gè)有限的集合 強(qiáng)窄帶來(lái)源和各向同性遠(yuǎn)lowpower 噪音[1]。在這部作品中，該模型的領(lǐng)域的方向性 摘要采用以下方法。首先，軸承的角度 空間是均勻采樣到大量的離散 角。其次，是認(rèn)為高能源 與強(qiáng)大的遠(yuǎn)源或低能耗 這與各向同性噪音收到傳感器 從每一個(gè)數(shù)組的方位角度離散。 ------------------------------------ 50674755@163.com
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- hou8444023 2010-01-19 00:00:00
- 本翻譯符合專業(yè)要求，請(qǐng)明鑒，不過(guò)賞分有點(diǎn)少了。 Spatial Compressive Sensing Approach For Field Directionality Estimation. 用于場(chǎng)方向性估計(jì)的空間壓縮傳感方法 I. INTRODUCTION 1. 引言 Variety of techniques for field directionality estimation were studied in literature [1]-[5]. Thus， a theoretical analysis of the relationship between the hydrophone array output and the noise field was conducted in [1]-[5]. 用于場(chǎng)方向性估計(jì)的多種技術(shù)在文獻(xiàn)中做了研究[1]-[5]。因此，對(duì)水聽器陣列輸出和噪聲場(chǎng)之間的關(guān)系進(jìn)行了理論的分析[1]-[5]。The developed techniques were based on the array beamformer output or the cross spectral matrix between outputs of array elements [4]-[5]. 所開發(fā)的技術(shù)是基于陣列波束形成器的輸出或陣列單元輸出之間的互功率譜矩陣[4]-[5]。The problem of a field directionality estimation in ocean， using horizontal line towed array was also addressed in literature [5]-[8]. 用水平線拖曳陣列在海洋中的場(chǎng)方向性估計(jì)問(wèn)題，在文獻(xiàn)中也用水平線拖曳陣列著重做了研究[5]-[8]。Recently， problems of direction of arrival and field directionality estimation for moving sensors arrays have attracted renewed interest [9]-[12]. 近年來(lái)，移動(dòng)的傳感器陣列的到達(dá)方向問(wèn)題和場(chǎng)方向性估計(jì)問(wèn)題已重新引起人們的興趣[9]-[12]。It was shown that an array motion can improve an array performance assuming temporal coherence of successive samples [10]-[11]. 已經(jīng)證明，假設(shè)相繼的樣本的時(shí)間相干性，那么一個(gè)陣列的運(yùn)動(dòng)可以改善一個(gè)陣列的性能[10]-[11]。In [12]， the wavefield sampling method that exploits the linear relationship between the noise field and the collection of beamformer outputs over various array orientations was proposed.在文獻(xiàn)[12]中，提出了探索噪聲場(chǎng)和在各個(gè)不同陣列取向上采集波束形成器輸出之間線性關(guān)系的波場(chǎng)取樣方法。 It was shown that the wavefield sampling (WS) method outperforms other tested methods. This algorithm was implemented via the recursive estimation method and its convergence to the unique solution was promised for a specific set of array orientations and beamformer look directions. 已經(jīng)證明，波長(zhǎng)取樣方法（WS）勝過(guò)其他被試驗(yàn)的方法。這一算法通過(guò)遞推估計(jì)法實(shí)施，并且它對(duì)唯yi解的收斂有望用于一組特定陣列取向和波束形成器觀察方向。However， a method for a proper array orientation and beamformer look direction sequence selection remains an open question. 然而，一種用于wan美陣列取向和波束形成器觀察方向順序選擇的方法仍然是一個(gè)公開的問(wèn)題。 The quality of the field directionality estimation is determined by the angular resolution. The higher angular resolution is， the more accurate estimation of the far field sources， and better detection performance can be achieved. 場(chǎng)方向性估計(jì)的質(zhì)量由角度分辨率決定。角度分辨率越高，遠(yuǎn)場(chǎng)源的估計(jì)精度就越高，并能達(dá)到越好的檢測(cè)性能。One of fundamental relations in the array signal processing is that the angular resolution is directly proportional to the number of the array elements [13]. 在陣列信號(hào)處理中的基本關(guān)系之一就是角度分辨率與陣列元件數(shù)成正比[13]。This relation motivates the desire for longer arrays that can achieve higher resolution. Unfortunately， the requirement contradicts the implementation and installation limitations that motivate shorter arrays. 這一關(guān)系激發(fā)了采用能達(dá)到較高分辨率的較長(zhǎng)陣列的欲望。不幸的是，這一要求與促進(jìn)較短陣列的實(shí)施和敷設(shè)是矛盾的。Moreover， implementation of longer arrays for maneuvering platforms such as unmanned underwater vehicles (UUV) can even be impossible [14]. 而且，對(duì)操縱平臺(tái)（例如無(wú)人潛水器（UUV））實(shí)施較長(zhǎng)陣列甚至?xí)遣豢赡艿腫14]。These contradictions motivate the quest for alternative array signal processing methods. Usually， the field directionality is modeled as a finite set of strong far-field narrow-band sources and an isotropic lowpower noise [1]. 這些矛盾激發(fā)了人們對(duì)可供選擇的陣列信號(hào)處理方法的尋找。通常，場(chǎng)方向性被建模為一組有限的強(qiáng)遠(yuǎn)場(chǎng)窄帶源和一個(gè)各向同性的低功率噪聲[1]。In this work， the model of the field directionality is adopted in the following way. 在本文中，場(chǎng)方向性的模型以以下方式被采用。First， the bearing angle space is uniformly sampled into a large number of discrete angles. 首先，象限角空間被均勻取樣成大量分離的角度。Next， it is assumed that ether the high energy that corresponds to the far-field strong sources or the low-energy that corresponds to the isotropic noise is received at the sensor array from every of these discrete azimuth angles. 其次，假設(shè)與遠(yuǎn)場(chǎng)強(qiáng)源相應(yīng)的高能量及與各向同性噪聲相應(yīng)的低能量都在傳感器陣列處被從這些分離的方位角的每一個(gè)角度被接收。（譯注：這里的ether漏字了，現(xiàn)按either翻譯，如實(shí)neither則意思相反）
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- 通信方面的英文文獻(xiàn)翻譯?。?
- 以下是文獻(xiàn)的一部分，愿意幫忙的高手留下郵箱，我把文件發(fā)給你，若能完成，加分：SpatialCompressiveSensingApproachForFieldDirectionalityEstimation.I.INTRODUCTIONVarietyoft... 以下是文獻(xiàn)的一部分，愿意幫忙的高手留下郵箱，我把文件發(fā)給你，若能完成，加分： Spatial Compressive Sensing Approach For Field Directionality Estimation. I. INTRODUCTION Variety of techniques for field directionality estimation were studied in literature [1]-[5]. Thus， a theoretical analysis of the relationship between the hydrophone array output and the noise field was conducted in [1]-[5]. The developed techniques were based on the array beamformer output or the crossspectral matrix between outputs of array elements [4]-[5]. The problem of a field directionality estimation in ocean， using horizontal line towed array was also addressed in literature [5]- [8]. Recently， problems of direction of arrival and field directionality estimation for moving sensors arrays have attracted renewed interest [9]-[12]. It was shown that an array motion can improve an array performance assuming temporal coherence of successive samples [10]-[11]. In [12]， the wavefield sampling method that exploits the linear relationship between the noise field and the collection of beamformer outputs over various array orientations was proposed. It was shown that the wavefield sampling (WS) method outperforms other tested methods. This algorithm was implemented via the recursive estimation method and its convergence to the unique solution was promised for a specific set of array orientations and beamformer look directions. However， a method for a proper array orientation and beamformer look direction sequence selection remains an open question. The quality of the field directionality estimation is determined by the angular resolution. The higher angular resolution is， the more accurate estimation of the far field sources， and better detection performance can be achieved. One of fundamental relations in the array signal processing is that the angular resolution is directly proportional to the number of the array elements [13]. This relation motivates the desire for longer arrays that can achieve higher resolution. Unfortunately， the requirement contradicts the implementation and installation limitations that motivate shorter arrays. Moreover， implementation of longer arrays for maneuvering platforms such as unmanned underwater vehicles (UUV) can even be impossible [14]. These contradictions motivate the quest for alternative array signal processing methods. Usually， the field directionality is modeled as a finite set of strong far-field narrow-band sources and an isotropic lowpower noise [1]. In this work， the model of the field directionality is adopted in the following way. First， the bearing angle space is uniformly sampled into a large number of discrete angles. Next， it is assumed that ether the high energy that corresponds to the far-field strong sources or the low-energy that corresponds to the isotropic noise is received at the sensor array from every of these discrete azimuth angles. 展開
2010-01-17 08:59:13
676
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- 求翻譯英文文獻(xiàn)
- 2.2. Material Characterizations. A field emission scanning electron microscope (SEM， JEOL 6701F) was used to investigate the morphologies， particle sizes of the samples. Transmission electron microscopy and elemental compositions of the ... 2.2. Material Characterizations. A field emission scanning electron microscope (SEM， JEOL 6701F) was used to investigate the morphologies， particle sizes of the samples. Transmission electron microscopy and elemental compositions of the samples were determined by JEM-2100F (JEOL) coupled with an energy-dispersive X-ray spectroscopy (EDX， Phoenix) system. Wide-angle and low-angle X-ray powder diffraction (XRD) of the as-obtained samples were recorded on a Rigaku D/max-2500 with Cu Kα radiation (λ = 1.540 56 ?) operated at 40 kV and 200 mA. Raman measurements were performed using a DXR from Thermo Scientific with a laser wavelength of 532 nm. To calculate the pore size distribution and pore volumes， the nitrogen absorption and desorption isotherms were measured at 77.3 K with an Autosorb-1 specific surface area analyzer from Quantachrome. The content of N in N-doped porous carbon was determined by NHC elemental analysis using Flash EA 1112. Thermogravimetric (TG) analysis of S/C composite was performed on TG/DTA 6300 in an N2 flow to obtain the S content in the composite. A four-contact method was applied to measure the powder electronic conductivity of porous carbons. The powder sample was pressed to disk at 4 MPa with two stainless-steel plungers， whose resistance was measured by a Keithley 2400 digital multimeter in fourwire mode. The conductivity of the sample was calculated according to the resistance and the size of the disk. Information of the surface elements was obtained by X-ray photoelectron spectroscopy (XPS) performed on the Thermo Scientific ESCALab 250Xi using 200 W monochromatic Al Kα radiation. The 500 μm X-ray spot was used for XPS analysis. The base pressure in the analysis chamber was about 3 × 10?10 mbar. All reported data of XPS binding energy are calibrated based on the hydrocarbon C 1s line at 284.8 eV from adventitious carbon. Spectra were fitted with Lorentzian?Gaussian functions and smart background using Thermo Avantage software. 展開
2014-12-28 15:14:51
571
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- 求助，英文文獻(xiàn)翻譯！
- 2. Experimental 2.1 Materials Nano-CaCO3 particles (D50: 30?70 nm by TEM (Fig. 1) and BET: ca.17m2·g-1) were supplied by Shanghai Zhuoyue Nanotech Corporation. Methyl methacrylate (MMA， Shanghai Lingfeng Chemicals) was purified ... 2. Experimental 2.1 Materials Nano-CaCO3 particles (D50: 30?70 nm by TEM (Fig. 1) and BET: ca.17m2·g-1) were supplied by Shanghai Zhuoyue Nanotech Corporation. Methyl methacrylate (MMA， Shanghai Lingfeng Chemicals) was purified by distillation under reduced pressure; potassium persulphate (K2S2O8， initiator， Shanghai Lingfeng Chemicals) was of chemical grade. Silane coupling agent A174 (γ-methacryloxypropyltrimethoxysilane) was purchased from Shanghai Yaohua Factory. Polyvinylchloride (PVC， WS-1000S) was supplied by Shanghai Chlor-Alkali Chemical Co.， Ltd. Fig. 1 Morphology of untreated CaCO3 nanoparticles. Fig. 2 Morphology of PMMA-coated CaCO3 nanoparticles. 2.2 PMMA emulsion polymerization on CaCO3 nanoparticles 2.2.1 Surface silanation of nano-CaCO3 particles The nano-CaCO3 particles were homogeneously dispersed in ethanol (solid content 20%) by a sonication dispersion equipment. The slurry was then heated to 80°C with stirring， and the silane coupling agent A174 (5%， calculated based on the weight of nano-CaCO3 particles) was added into the slurry. After the slurry was stirred for 120 min at 80°C， it was filtered and the filter cake was then dried at 120°C in low vacuum for 120 min to obtain silanated CaCO3 powders. 展開
2011-05-16 00:26:36
467
4
- 求助，英文文獻(xiàn)翻譯~
- PMMA has good compatibility with PVC due to specific interaction of a hydrogen bonding type between carbonyl groups (C=O) of PMMA and hydrogen from (CHCl) groups of PVC (Belhaneche-Bensemra et al.， 2002; Ramesh et al.， 2002). Zhou et al... PMMA has good compatibility with PVC due to specific interaction of a hydrogen bonding type between carbonyl groups (C=O) of PMMA and hydrogen from (CHCl) groups of PVC (Belhaneche-Bensemra et al.， 2002; Ramesh et al.， 2002). Zhou et al. (2001) studied the relationship between the coating thickness of PMMA on the surface of talc and mechanical properties of PMMA-g-talc/PVC composites， and found that there existed a critical thickness. Xie (2001) found that the PMMA coating on talc improved the dispersion of talc in the PVC matrix and enhanced the interfacial adhesion between talc and PVC. There appears to be a critical coating thickness of PMMA on the talc surface for optimum toughening. Quan et al. (2002) reported improved toughness and intension of the PVC composites filled with CaCO3/ACR core-shell complex particles prepared by in-situ emulsion polymerization of acrylic ester. In the present work， PMMA coated on the surface of CaCO3 nanoparticles by in-situ emulsion polymerization was characterized by FT-IR and 1H-NMR. The effects of PMMA thickness and particle fraction on the mechanical properties of PMMA-coated CaCO3 /PVC nanocomposites were also investigated. 展開
2011-05-16 04:20:15
525
4
- 測(cè)序方面的生物專業(yè)英文句子翻譯
- The cDNA and gene sequences currently available includes 31，741 unique sequences assembled from 217，519 high quality 454 sequencing reads.這句怎么翻譯？尤其是high quality 454 sequencing reads具體怎么翻譯
2012-10-02 13:55:39
543
4
- 納米材料英文文獻(xiàn)加翻譯
2013-06-26 12:47:02
489
1
- 誰(shuí)能翻譯這段英文，化學(xué)專業(yè)方面的，很難
- This work examines the behaviour of fluorine modified b-PbO2 electrodes in the processes of O2 and O3 evolution in sulphuric acid. The electrochemical kinetic analyses of these processes are based on quasi-steady-state polarisation and impe... This work examines the behaviour of fluorine modified b-PbO2 electrodes in the processes of O2 and O3 evolution in sulphuric acid. The electrochemical kinetic analyses of these processes are based on quasi-steady-state polarisation and impedance data. The good agreement between the two sets of measurements allows some basic conclusions to be drawn. In particular， the O2 evolution process is always inhibited at F-doped PbO2 electrodes， and impedance results suggest possible changes in the mechanism， with electrodesorption of intermediates becoming more important as the concentration of the doping element increases. The interpretation of the data for the less positive potentials region invokes the specific adsorption of SO4 as a factor influencing the kinetics of O2 evolution. The current efficiency for O3 formation as a function of the amount of NaF added to the PbO2 growth solution reaches a maximum for a concentration of 0.01 mol dm 3. A plausible cause for the decrease on the higher concentration side is the discharge of adsorbed SO4 2 (or HSO4 ) eventually yielding persulphate. This reaction is known to be favoured in the presence of a relatively high amount of fluoride in the electrolyte. An analysis of the results of modified neglect of diatomic differential overlap (MNDO) calculations on Pb cluster models and of X-ray photoelectron spectroscopy (XPS) data suggests that the coverage by weakly adsorbed oxygen species (OH and H2O) is an important parameter that is influenced by F-doping. ? 1999 Elsevier Science Ltd. All rights reserved. 展開
2009-02-21 00:33:53
464
6
- 急求！基于單片機(jī)半導(dǎo)體激光器脈沖驅(qū)動(dòng)方面的英文文獻(xiàn)
- 本人做論文，急求基于單片機(jī)半導(dǎo)體激光器脈沖驅(qū)動(dòng)方面的英文文獻(xiàn)，帶中文翻譯！不要中文直接翻譯過(guò)來(lái)哦！是要英文原版的！
2010-06-19 16:47:57
476
2
- 有關(guān)機(jī)械液壓方面的英文資料及翻譯，翻譯的字?jǐn)?shù)5000以上！謝謝?。?
2011-03-15 06:12:52
469
4
- 幫忙翻譯一段關(guān)于方酸染料合成的的英文文獻(xiàn) 急急急
- Synthesisofsquarainedyeswasreportedatleastin1966。Theyarederivedfromsquaricacidwhichundergoesanelectrophilicaromaticsubstitutionreactionwithananilineoranotherelectronrich... Synthesis of squaraine dyes was reported at least in 1966 。They are derived from squaric acid which undergoes an electrophilic aromatic substitution reaction with an aniline or another electron rich derivative to form a highly conjugated product with extensive charge distribution. For instance， squaraine dyes are also formed via reaction of squaric acid or its derivatives with so-called "methylene bases" like 2-methyl-indolenines， 2-metyl-benzthiazoles or 2-methyl-benzo-selenazoles. Indolenine-based squaraines combine good photostability including high quantum yields when bound to proteins and reactive versions of these dyes are commonly used as fluorescent probes and labels for biomedical applications . 展開
2011-05-20 09:09:32
331
2
- 誰(shuí)能幫我翻譯一下這段英文文獻(xiàn)啊
- Fig. 1 shows that diamond particles are dispersed in the copper matrix. Since the diamond particles are easy to be stripped off during mechanical polishing， small pits are left on the surface of samples. When the samples were analyzed b... Fig. 1 shows that diamond particles are dispersed in the copper matrix. Since the diamond particles are easy to be stripped off during mechanical polishing， small pits are left on the surface of samples. When the samples were analyzed by electron probe for carbon， the particles displayed high carbon peaks， as shown in Fig. 2. Fig. 3 exhibits the analyzed result for extracted product of the copper–diamond composite by X-ray diffraction (XRD) analysis. It is shown that three dif- fraction peaks exist， shown as A， B and C， respectively. The interplanar distances corresponding to the three peaks and standard ones for diamond are compared in Table 1. The measured values of the interplanar distances are in good agreement with the standard ones， demon- strating that the extracted product should be the carbon in diamond state. Fig. 4(a) gives a TEM micrograph showing distribution and morphology of diamond particles (indicated as A， B， and C) in the copper–diamond composite. The calibration of interplanar distance for diffraction rings in Fig. 4(b) was given in Table 2. Compared to Table 1， it is also demon- strated that the calibrated interplanar distances for the diffraction rings conform to the standard ones of diamond. Therefore， it is believed that the graphitization of diamond particles hardly occurs after sintering at 1150–1220 K in the copper–diamond composite. Although diamond is a metastable allotropic modifica- tion of carbon， the graphitization of diamond particles in the copper–diamond composite did not occur， or the degree of graphitization was too small to be found. It is believed that the beginning temperature of graphi- tization would be associated with the purity of diamond powders. The impurities such as some metallic elements reduce the beginning temperature of diamond graphitiza- tion. When diamond is fabricated by the static synthesis method， Fe and Ni are often used as catalysts and are present in diamond as impurities to decrease the beginning temperature of graphitization [6]. It is understandable that both for the graphitization and its reverse reactions， their activation energies can be decreased by catalytic agents. Compared with the diamond fabricated by static synthesis， the diamond powders prepared by explosion method do not contain metallic impurities， thus leading to an obvious increase in the beginning temperature of graphitization. Hence， the detonation synthetic diamond might be more resistant to graphitization and probably suitable for the electric contact materials. 展開
2011-03-22 08:43:56
449
2
- 文獻(xiàn)求翻譯
- Since the formation of a titanacyclopropane en route to cyclopropylamines can only occur with alkylmagnesium halides that contain a b-hydrogen atom， Grignard reagents without b-hydrogens appeared to be the most promising reagents for th... Since the formation of a titanacyclopropane en route to cyclopropylamines can only occur with alkylmagnesium halides that contain a b-hydrogen atom， Grignard reagents without b-hydrogens appeared to be the most promising reagents for the synthesis of primary tert-alkylamines from nitriles (Scheme 1). Thus propionitrile (1a)， phenylmagnesium bromide (2) and Ti(Oi-Pr)4 were chosen to optimize the reaction conditions. In the protocol for the synthesis of cyclopropylamines，10 Ti(Oi-Pr)4 is already present in the diethyl ether solution of a nitrile， before two equivalents of the Grignard reagent are added. As this did not appear to be optimal for the synthesis of primary tertalkylamines， the Grignard reagent was added before Ti(Oi-Pr)4. With 2 equivalents of PhMgBr， 0.1 equivalent of Ti(Oi-Pr)4， and 1 equivalent of propionitrile (1a)， the primary tert-alkylamine 8a was not formed at all. With an equimolar quantity of Ti(Oi-Pr)4， the amine 8a was produced in a low yield (11%) but with 1 equivalent of Ti(Oi- Pr)4 and 3 equivalents of the Grignard reagent 2， a 60% yield of 8a was obtained. Monitoring of the reaction by workup of aliquots of the reaction mixture showed that the first addition of 2 to form the N-magnesio derivative of the corresponding imine was rapid， whereas the subsequent second addition of the Grignard reagent 2 required heating under reflux for up to 24 hours. In tetrahydrofuran instead of diethyl ether， the amine 8a was formed in a very low yield， if at all. 展開
2012-08-31 01:19:05
451
5
- 求翻譯文獻(xiàn)
- Anionsarecommonlyfoundintheenvironmentandbiologicalsystems.Forinstance，fluorideiswidelyusedindentalcareapplicationsandexhibitsinhibitionofcertainenzymefunctions.1Inadditi... Anions are commonly found in the environment and biological systems. For instance， fluoride is widely used in dental care applications and exhibits inhibition of certain enzyme functions.1 In addition to playing a central role in biological regulation， chloride is also a major groundwater contaminant that can corrode steel and concrete.2 Thyroid hormone synthesis largely determines iodine content.3 Acetate is a possible tracer for malignancies and has been extensively investigated in prostate cancer and its metastases.4 Phosphate ion is biologically and environmentally significant.5 Cyanide exerts adverse effects on human health as well as environment at low concentrations. Determining anions concentration is thus of primary concern in many areas， including food processing， industry， and clinic analysis.6 However， hydrophilic anions， such as F- and Cl-， form strong hydrogen bonds with protic solvents. Therefore， developing fluorescent probes based on electrostatic interactions for anions functioning in polar protic solvents is both challenging and currently infeasible. 展開
2009-12-15 12:42:12
450
6
- 做通信方面的軟件開發(fā)公司有哪些？
- 比如華為？... 比如華為？ 展開
2010-03-30 08:23:08
439
3
- 幫忙翻譯一下化工方面的單詞 英語(yǔ)
- 堿值測(cè)定器試劑移液管錐形瓶酸式滴定管甲基黃溴甲酚綠混合指示劑鹽酸標(biāo)準(zhǔn)溶液摩爾/升酸式滴定管... 堿值 測(cè)定器 試劑 移液管 錐形瓶 酸式滴定管 甲基黃溴甲酚綠混合指示劑 鹽酸標(biāo)準(zhǔn)溶液 摩爾/升 酸式滴定管 展開
2010-01-17 06:38:39
674
5
- 翻譯段文獻(xiàn)麻煩
- Eventhoughfluorescentprobesforcopperionhavebeenextensivelyexploredowingtobiologicalsignificanceofthismetalion，4therearestillonlyafewexamplesof“off-on”typesensorsavailab... Even though fluorescent probes for copper ion have been extensively explored owing to biological significance of this metal ion，4 there are still only a few examples of “off-on” type sensors available in aqueous systems.5 Furthermore， only a few ratiometric fluorescent probes for Cu2+ have been found in the literature due the fluorescence quenching nature of paramagnetic Cu2+，6 and most of them were working only in pure organic solvents. Ratiometric fluorescent measurements observe changes in the ratio of the intensities of the emission at two wavelengths. Thus， ratiometric fluorescent sensors have an important feature that they can be used to evaluate the analyte concentration and provide built-in correction for environmental effects. On the other hand， rhodamine derivatives are nonfluorescent and colorless， whereas ring-opening of the corresponding spirolactam gives rise to strong fluorescence emission and a pink color. Recently， a spirolactam (nonfluorescent) to ringopened amide (fluorescent) process was utilized for the detection of metal ions.5a，b，d，e，7 We introduced rhodamine fluorophore onto the pyrene moiety， which was utilized as a selective fluorescent and colorimetric sensor for Cu2+ in aqueous solution. Among the various metal ions， the chemosensor PRC displayed highly selective ratiometric changes upon the addition of Cu2+. As expected， the pyrene moiety served successfully as a source of these ratiometric changes. As far as we are aware， PRC is the first ratiometric sensor based on rhodamine derivative. For comparison， pyrene-based compound P4 was synthesized to test the fluorescence change with Cu2+. 展開
2009-12-23 07:28:19
484
6
- 哪位大神有月球土壤方面的文獻(xiàn)和資料
- 主要用于地質(zhì)鉆探方面的，例如土壤顆粒，巖性，硬度什么的~小弟先在這兒跪謝了... 主要用于地質(zhì)鉆探方面的，例如土壤顆粒，巖性，硬度什么的~小弟先在這兒跪謝了 展開
2013-05-06 02:52:03
472
2
- 翻譯以下英文：
- The standard error of the mean (SEM) is a measure of how far your sample mean is likely to be from the true population mean. The SEM is calculated by this equation:SEM=SD/N. With large samples， the SEM is always small. By itself， the SEM i... The standard error of the mean (SEM) is a measure of how far your sample mean is likely to be from the true population mean. The SEM is calculated by this equation:SEM=SD/N. With large samples， the SEM is always small. By itself， the SEM is difficult to interpret. It is easier to interpret the 95% confidence interval， which is calculated from the SEM. 展開
2007-11-15 02:56:39
545
3
- 求助！！！通信類專業(yè)翻譯
- 圖像處理系統(tǒng)構(gòu)成該系統(tǒng)硬件主要包括光源照明系統(tǒng)、CCD高速攝像機(jī)、圖像采集卡、圖像處理卡DSP芯片和執(zhí)行機(jī)構(gòu)CPLD(復(fù)雜可編程邏輯器件)等；而軟件嵌入在圖像處理卡中，包含有效的異纖... 圖像處理系統(tǒng)構(gòu)成 該系統(tǒng)硬件主要包括光源照明系統(tǒng)、CCD高速攝 像機(jī)、圖像采集卡、圖像處理卡DSP芯片和執(zhí)行機(jī)構(gòu) CPLD(復(fù)雜可編程邏輯器件)等；而軟件嵌入在圖像 處理卡中，包含有效的異纖檢測(cè)與識(shí)別算法．該算法可 實(shí)現(xiàn)對(duì)圖像中各種異纖的分析、識(shí)別、統(tǒng)計(jì)和決策．高 速、高抗干擾的圖像處理硬件保證該系統(tǒng)在工業(yè)應(yīng)用 中的實(shí)時(shí)性與可靠性要求． 2．1 系統(tǒng)硬件結(jié)構(gòu)框圖 該設(shè)計(jì)方案為基于DSP+CPI D結(jié)構(gòu)的數(shù)字圖像 處理系統(tǒng)．它需要完成圖像采集、數(shù)字化處理、圖像處 理、圖像分析、圖像顯示等功能．本系統(tǒng)以TI公司的 TMS320DM642作為主處理器. 系統(tǒng)的整體工作流程為：兩側(cè)的線掃CCD攝像機(jī) 把采集到的圖像信號(hào)經(jīng)TVP5150視頻解碼芯片轉(zhuǎn)化 為ITu — RBT．656格式，內(nèi)嵌同步信號(hào)發(fā)送到 DM642的VP口．圖像的行同步、列同步、場(chǎng)同步信號(hào) 均內(nèi)嵌在視頻數(shù)據(jù)流中．對(duì)于片內(nèi)存儲(chǔ)資源有限的高 速DSP，存儲(chǔ)視頻數(shù)據(jù)需借助外部存儲(chǔ)空間．為了提 高系統(tǒng)實(shí)時(shí)處理能力，數(shù)據(jù)傳輸由EDMA完成，CPU 只用于數(shù)據(jù)計(jì)算．采集視頻數(shù)據(jù)經(jīng)EDMA 存儲(chǔ)到 SDRAM 中，或把數(shù)據(jù)從視頻通道傳送到片內(nèi)RAM 中進(jìn)行運(yùn)算．DSP(DM642)對(duì)圖像進(jìn)行分析、識(shí)別、定 位等算法處理，對(duì)異纖進(jìn)行分類識(shí)別，經(jīng)EDMA、 SAA7121H視頻編碼器，將其信號(hào)轉(zhuǎn)換為PAL(50 HZ)制式或NTSC(60 HZ)制式送到外部液晶屏進(jìn)行 顯示． 其中SDRAM對(duì)應(yīng)DM642上的CE0映射的地址 空間，使用2片32位數(shù)據(jù)總線的同步動(dòng)態(tài)RAM，高 32位存儲(chǔ)在一片RAM 中，低32位存儲(chǔ)在另一片 RAM 中，滿足DM642 64位數(shù)據(jù)總線要求．SDRAM 在CE0子空間的具體定位為：0x80000000H 一 0x81FFFFFFH．系統(tǒng)的代碼固化在FLASH 中， FI ASH 在CE1子空間占據(jù)的具體空間定位為： 0x90000000H一0x9007FFFFH．DM642只提供20根 外部地址總線，所以CE1子空間Z大尋址范圍為1 M ×8位，SEED—VPM642板上CE1子空間除了分配 給FLASH 以外，還分配給狀態(tài)／控制寄存器、UAR— TA、UARTB等資源使用，其中FLASH 只占CE1子 空間的前一半的尋址空間，即Z大可尋址范圍為512 K×8位，而FLASH 的設(shè)計(jì)容量為4 M×8位，所以 采用分頁(yè)技術(shù)實(shí)現(xiàn)對(duì)FLASH 的訪問(wèn)，即將整個(gè)4 M ×8位的FLASH分成8個(gè)512 K×8位的頁(yè)，而頁(yè)地 址PA21、PA20、PAl9則由頁(yè)地址寄存器提供(頁(yè)地 址寄存器位于CPLD中)．CF卡接在EMIF卡的CE2 空間，用來(lái)存放特征庫(kù)和識(shí)別結(jié)果．CPLD是在傳統(tǒng)的PAL、GAL基礎(chǔ)上發(fā)展而來(lái) 的．與FPGA相比，CPLD比較適合計(jì)算機(jī)總線控制、 存儲(chǔ)控制器、DMA控制器、CACHE控制器、圖形控制 器等I／O密集型應(yīng)用，且具備無(wú)須外部配置ROM、時(shí) 延可預(yù)測(cè)等特性．目前的CPLD 普遍基于E2和 FLASH 電可擦技術(shù)，可實(shí)現(xiàn)100次以上擦寫循環(huán)．考 慮到該系統(tǒng)設(shè)計(jì)方案，選用了型號(hào)為CY37O64P1OO的 復(fù)雜可編程邏輯器件，工作電壓為3．3 V． 2．2 異纖識(shí)別軟件的開發(fā) 在軟件開發(fā)方面，以闡述C6000的CCS(Code Composer Studio)集成開發(fā)環(huán)境為主線．應(yīng)用于 C6000的CCS是C60OO系列DSP的主流開發(fā)工具， 目前已推出3．3版本． CCS是TI公司推出的一個(gè)集成性DSP軟件開發(fā)工具． 在一個(gè)開放式的插件(plug—in)結(jié)構(gòu)下，CCS內(nèi) 部集成了以下軟件工具： (1)C6000代碼產(chǎn)生工具(包括C6000的C匯編 器、匯編優(yōu)化器、匯編器和連接器)； (2)軟件模擬器； (3)實(shí)時(shí)基礎(chǔ)軟件DSP／BIOS； (4)主機(jī)與目標(biāo)機(jī)之間的實(shí)時(shí)數(shù)據(jù)交換軟件RT— DX： (5)實(shí)時(shí)分析和數(shù)據(jù)可視化軟件． 在CCS下，開發(fā)者可以對(duì)軟件進(jìn)行編輯、編譯、調(diào) 試、代碼性能測(cè)試和項(xiàng)目管理等所有工作．此外，它還 提供了實(shí)時(shí)分析和數(shù)據(jù)可視化功能，大大降低了DSP 系統(tǒng)開發(fā)的難度，使開發(fā)者可以將精力集中在應(yīng)用開 發(fā)上 展開
2009-03-08 16:18:40
760
1
- 急求翻譯下面這段測(cè)繪工程方面的文章
- REAL-TIME KINEMATIC GPS Real-Time Kinematic (RTK) is Trimble Navigation's Site Surveyor System available as a standard option upgrade to Trimble's 4000 series SE and SSE receivers. The Medicine Bow National Forest uses 4000 SSE and SE rece... REAL-TIME KINEMATIC GPS Real-Time Kinematic (RTK) is Trimble Navigation's Site Surveyor System available as a standard option upgrade to Trimble's 4000 series SE and SSE receivers. The Medicine Bow National Forest uses 4000 SSE and SE receivers in it's Boundary Management program. The use of RTK enables a surveyor to determine a corner's position， establish a corner without having to make traditional corner moves or to mark and post line as quickly as the surveyor could walk， all without having to post-process the data. The surveyor using RTK can perform corner search within a meter or a couple of centimeters of the true location without the need to traverse down the line. For some survey applications traditional kinematic GPS field procedures are preferred， since many points can be observed in a short period of time with occupation times of a minute or less. However until now， kinematic surveying required post-processing before the results were available. This made field stakeout of corner positions， corner search， line marking and posting， and evaluation of coordinate accuracy in the field impossible to do using kinematic techniques (Curry et al 1993). Now， the use of RTK technology makes these impossible traditional kinematic tasks possible. What is RTK? RTK is currently carrier phase observations processed (corrected) in real-time resulting in position coordinates to a 1-2 centimeter accuracy level being available to the surveyor in the field. In other words， what the surveyor sees is what he gets. RTK， consists of two or more GPS receivers， three or more radio-modems， a "fixed-plate initializer" ， and a handheld survey data collector/computer (TDC1). In RTK， one receiver occupies a known reference station and broadcasts a correction message (Compact Measurement Record or CMR2) to one or more roving receivers. The roving receivers process the information to solve the WGS-84 vectors by solving the integers in real-time within the receiver to produce an accurate position relative to the reference station. Precision of RTK is +/-2 cm + 2 ppm， with 1 ppm equating to 1 mm per 1 km (Trimble Navigation， 1993). The TDC1 is used to graphically display the processed results of the surveyors current position on the ground at that moment. The TDC1 has the capability for the surveyor to navigate within a couple of centimeters to a known or unknown coordinate position using Local， State Plane or Geographic coordinates. In real-time positions may be logged in the field， inverses performed， attributes (features) recorded， azimuths and distances between points calculated， and corners located. RTK， as with traditional kinematic GPS procedures， currently requires continuous satellite lock to be maintained. This restriction allows for RTK to be most effective in a non-canopied， no obstructions environment. 展開
2009-06-04 09:20:37
550
1
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