求助，英文文獻(xiàn)翻譯~
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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
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- sunnyyaokongqi 2011-05-24 00:00:00
- 二樓翻譯機(jī)連回車都懶得去么囧
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- ttnn123456 2011-05-24 00:00:00
- PMMA具有良好的兼容性與PVC由于特定 羰基之間的相互作用氫鍵類型 組（C = O等）的聚甲基丙烯酸甲酯和氫（）組 聚氯乙烯（Belhaneche - Bensemra等，2002;。。拉梅什等人， 2002年）。周等人。 （2001年）之間的關(guān)系研究 對滑石粉和表面涂層厚度的PMMA 復(fù)合材料力學(xué)性能的PMMA-g-talc/PVC， 發(fā)現(xiàn)存在一個(gè)臨界厚度。謝（2001） 發(fā)現(xiàn)對滑石涂層改善了分散聚甲基丙烯酸甲酯 滑石粉在PVC基體，提高了界面 滑石粉和PVC之間的粘附。似乎有一 PMMA的關(guān)鍵涂層厚度對滑石粉表面 Z佳增韌。泉等。 （2002年）報(bào)告改善 充滿韌性和強(qiáng)度的PVC復(fù)合材料 CaCO3/ACR核殼復(fù)合粒子的制備 原位聚合丙烯酸酯乳液。 在目前的工作，聚甲基丙烯酸甲酯的表面涂覆 原位乳液聚合納米碳酸鈣 利用FT - IR和核磁共振。的影響 有機(jī)玻璃厚度和粒子分?jǐn)?shù)對力學(xué) 性能的聚甲基丙烯酸甲酯包覆碳酸鈣/聚氯乙烯納米復(fù)合材料 進(jìn)行了研究。
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- wo007yili 2011-05-17 00:00:00
- 由于PMMA（聚甲基丙烯酸甲酯）的羰基與PVC（聚氯乙烯）中CHCl基團(tuán)上的H可以形成氫鍵這種特殊的交互作用，因此，聚甲基丙烯酸甲酯與聚氯乙烯有很好的兼容性（Belhaneche-Bensemra等人，2002；Ramesh等人，2002）。周等人（2001）研究了在云母表面上PMMA的涂膜厚度與PMMA-g-talc/PVC這種復(fù)合材料的機(jī)械性能之間的關(guān)系，并且發(fā)現(xiàn)存在一個(gè)臨界厚度。謝（2001）發(fā)現(xiàn)在云母上的PMMA膜，可以提升在PVC基質(zhì)中云母的分散性，并且提高了云母與PVC之間的界面吸附。在云母表面，似乎存在一個(gè)臨界PMMA膜厚度，使得材料有Z佳的增韌效果。Quan等人（2002）記錄了用丙烯酸酯原位乳液聚合作用制備的CaCO3/ACR核殼復(fù)合顆粒填充而改良了韌性和強(qiáng)度的PVC復(fù)合材料。Z近研究工作中，把由原位乳液聚合作用得到的CaCO3納米顆粒表面的PMMA膜用傅里葉變換紅外光譜和核磁共振儀圖譜進(jìn)行了表征。同時(shí)，也研究了PMMA厚度和顆粒多少對PMMA-膜 CaCO3 /PVC納米復(fù)合材料機(jī)械性能的影響。 "talc"我翻譯為“云母”，不知對嗎？
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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
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- 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
523
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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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- 納米材料英文文獻(xiàn)加翻譯
2013-06-26 12:47:02
489
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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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- 誰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
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- 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
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- 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
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- 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
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- 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
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- 求助翻譯
- 問題一：請問“在GF254硅膠板上，取樣點(diǎn)板，在254nm紫外光下觀察結(jié)果”這句話該如何翻譯？ZD是不知道“取樣點(diǎn)板”怎么翻譯問題二：麻煩高手幫忙翻譯一下2Results2.1柱色譜分離結(jié)果The... 問題一： 請問 “在GF254硅膠板上，取樣點(diǎn)板，在254 nm紫外光下觀察結(jié)果” 這句話該如何翻譯？ ZD是不知道“取樣點(diǎn)板”怎么翻譯 問題二：麻煩高手幫忙翻譯一下 2 Results 2. 1 柱色譜分離結(jié)果 The results of separation by column chromatography 柱色譜分離過程中，氯仿∶甲醇95∶5和90∶10洗脫出來的流分經(jīng)過反復(fù)的硅膠柱色譜分離純化得到組分C3。 2. 2 薄層色譜檢測結(jié)果 The results of Thin-layer chromatography. 組分C3在GF254硅膠板上展開后，可在254nm紫外燈下直觀觀測為單點(diǎn)，見圖1。 2. 3 GX液相色譜分析和制備單體化合物 對組分C3 進(jìn)行GX液相制備，色譜圖顯示有4個(gè)色譜峰(見圖2) ，分離效果較好，收集4個(gè)單峰組分，得到4個(gè)化合物1～4，對以上4個(gè)化合物進(jìn)行GX液相分析，均為單峰，見圖3～4。 3 化合物的結(jié)構(gòu)鑒定 通過制備液相收集得到4個(gè)化合物，對其中3個(gè)化合物進(jìn)行結(jié)構(gòu)鑒定: 化合物1， 淡黃色晶體， UV λmax nm (logε) : 248 nm。E IMS，m / z 501. 3 [M + 1 ] + ，分子量為500。化合物1氫譜顯示7個(gè)甲基信號;δ1. 02， 0. 93， 0. 78 ( each 3H， s) ， 0. 89 ( 3H， d， J =6. 4Hz) ， 1. 23， 1. 25 ( each 3H， d， J = 5. 2Hz) ， 1. 22(3H， s) ，一個(gè)連氧碳上的氫信號δ3. 23 (1H， dd， J= 10 Hz) ，符合三萜化合物的結(jié)構(gòu)，可以證明化 合物1為三萜類化合物。 化合物2， UV λmax nm ( logε) : 250 nm。E IMS，m / z 515. 3 [M + 1 ] + ，分子量為514?；衔?的氫譜顯示7個(gè)甲基信號δ0. 77， 0. 94， 1.01， 1. 22， 1. 23 (3H， s) ， 0. 82 (3H， d， 10. 2 Hz) ，一個(gè)連氧碳上的氫信號δ3. 22 ( 1H， dd， J = 10. 5Hz) ，一個(gè)甲氧基上的氫信號δ3. 66 (3H， s) ，符合三萜化合物的結(jié)構(gòu)，可以證明化合物2為三萜化合物。 化合物3， UV λmax nm ( logε) : 254 nm。EIMS，m / z 531. 2 [M + 1 ] + ，分子量為514。化合物2 的氫譜(見附錄)顯示7 個(gè)甲基信號δ0.78， 0. 82， 0. 87， 1. 03， 1. 24， 1. 31 ( 3H， s) ， 1. 17(3H， d， 6. 6 Hz) ，一個(gè)乙酰基上的氫信號2. 10(3H， s) ，一個(gè)甲氧基團(tuán)的氫信號3. 68 (3H， s) ，符合三萜化合物的結(jié)構(gòu)，可以證明化合物3為三萜化合物。 化合物4結(jié)構(gòu)較復(fù)雜，不能確定是三萜化合物。 二樓的辛苦了，非常感謝你的回答。不過好像沒有明白我的意思，而且有g(shù)oogle之嫌。 展開
2009-05-07 18:35:24
770
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- 環(huán)境英語文獻(xiàn)翻譯 急用
- Thereisagrowinginterestindeterminingmercury(Hg)levelsinthemarineenvironmentaswellasinfishforhumanconsumption.Methylmercury(MeHg)inparticularisthemosttoxicandbioaccumulati... There is a growing interest in determining mercury(Hg) levels in the marine environment as well as in fish for human consumption. Methyl mercury(Me Hg)in particular is the most toxic and bioaccumulative form of mercury in food webs and it is the predominant chemical form making up 80%-90% of the total mercury present in fish muscle tissue.Hence，fish and other organisms at the end of the food chain constitute the major source of MeHg in the human . As outcome of this risk，MeHg has been classically monitored in fish， and methodologies for mercury speciaion have increased significantly since the early 1990s. Currently， microwave-assisted extraction (MAE) has provided an efficient alternative strategy to conventional techniques for solvent extraction of a large amount of organometals compounds.The analytical techniques most frequently applied for Hg speciation analysis involve GC(GasChromatography) ， GC-CICP-MS(Gas Chromatography -CInductively Coupled Plasma Mass Spectrometry) supercritical fluids chromatography (SFC)，ion chromatograph(IC)， HPLC-CCVAAS(High Performance Liqui Chromatography-Cold Vapor Atomic Absorption Spectrometry) or ICP-MS systems .Several authors recommended a back-extraction of mercury species from organic solvents to cysteine or sodium thiosulphate aqueous solutions .Because MeHg is the most common organomercury compound in biological materials ，here we offer a new simple and cost-effective method to determine MeHg. Basically， this method combines the microwave assisted extraction followed by clean-up with cysteine acetate solution and MeHg quantification by a direct mercury analyzer (DMA). 展開
2009-05-18 11:22:05
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- 求達(dá)人 翻譯下英文文獻(xiàn) 關(guān)于 光系統(tǒng)Ⅱ和除草劑 通順Z重要
- PhotosystemIIisthemulti-enzymaticchlorophyll-proteincomplex(water-plastoquinoneoxido-reductase)locatedinthethylakoidmembraneofalgae，cyanobacteriaandhigherplants.Itisanint... Photosystem II is the multi-enzymatic chlorophyll-protein complex (water-plastoquinone oxido-reductase) located in the thylakoid membrane of algae， cyanobacteria and higher plants. It is an integral part of the electron transport chain that catalyses primary charge separation. This protein complex consists of over 25 polypeptides， which make up a light-harvesting chlorophyll protein complex (LHCII)， a reaction centre and the water-splitting system， also called the oxygen evolving complex (OEC). The PSII complex also contains the target site of the most widely used photosynthetic herbicides."^ The preparation of a biosensor for the detection of polluting compounds is based on the specific characteristics of PSII. Under illumination PSII drives electron transfer which is inhibited by specific chemical compounds (e.g.， herbicides). Thus， the photosynthetic membrane isolated firom higher plants and photosynthetic micro-organisms， immobilised and stabilised， will serve as the biosensor biomediator. The effect of compounds that alter or inhibit photosynthetic activity， measured as oxygen evolution， electron transport or fluorescence can then be translated and monitored by amperometric or optical systems. Recent experiments that were performed by our this team resulted in amperometric， potentiometric， optical biosensors for herbicides based on isolated and immobilised PSII particles exhibiting stable biological material and a highly sensitive monitoring response (limit of detection in the nanomolar range and for diuron herbicide in the picomolar range).^'^ However， the system is specific to photosynthetic herbicides but not very selective since several classes of compounds (herbicides represented by triazines， ureas， diazines， phenols) can bind to proteins of the PSII complex， most of them to the Dl protein of the reaction centre. 展開
2010-04-30 16:23:35
430
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- 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
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- 波譜英文文獻(xiàn)在哪里下載?
2010-12-08 02:02:14
441
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- 化工類英文科技文獻(xiàn)譯中文
- There is a fair body of literature concerning the electroreduction of glucose. This has been reviewed by Fedoronko. He divided his review into the polarographic work and that done on solid electrodes. The polarographic studies form a cohere... There is a fair body of literature concerning the electroreduction of glucose. This has been reviewed by Fedoronko. He divided his review into the polarographic work and that done on solid electrodes. The polarographic studies form a coherent picture， in which the experimentally observed data， which take the form of a plateau， not diffusion controlled， are explained in terms of a rate-determining step of mutarotation from the cyclic (inactive) form of the sugar to the linear (electroactive) form. The process is known to be both acid and base catalyzed， and has been reviewed by Capon. It is generally assumed that no hydrogen evolution takes place in the polaro- graphic plateau region. 翻譯通順有加分！謝謝大家！不需要機(jī)器翻譯的！ 展開
2009-03-05 08:04:04
354
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- 數(shù)據(jù)采集的英文怎么翻譯？
2010-07-05 09:53:28
414
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- 翻譯英文~專業(yè)類的
- Whilegraphene，acarbon-basedtwo-dimensionalnanomaterials，hasreceivedanupsurgeofinterest，[1]self-assemblyofsmallorganicandorganometallicmoleculesinto2Dnanostructurescouldal... While graphene， a carbon-based two-dimensional nanomaterials， has received an upsurge of interest，[1] self-assembly of small organic and organometallic molecules into 2D nanostructures could also be harnessed to develop new classes of functional supramolecular nanomaterials.[2] In principle， quasi-2D lamellae or nanosheets are planar structures having a thickness less than 100 nm and lateral dimensions a few orders of magnitude greater than their thickness. Control over the bilateral intermolecular noncovalent interactions is anticipated to organize small molecules into regular 2D nanostructures， which has been a formidable challenge yet to be achieved. Recently， Shelnutt and co-workers obtained discrete porphyrin nanosheets reprecipitated from their solutions;[3] Sathish and co-workers constructed hexagonal C60 nanosheets using a liquid–liquid interfacial precipitation method;[4] the groups of Yao[5] and Hu[6] prepared singlecrystalline nanosheets of polycyclic aromatics using a surfactant- assisted reprecipitation and a physical vapor transporting method， respectively; and Zhang and co-workers suggested that molecules with intramolecular charge-transfer dipole moments could be grown into quasi-2D nanostructures.[7] Moreover， some amphiphiles and organogelators were found to self-organize into sheet-like nanostructures in contact with solvents.[8] Despite these advances， templateand surfactant-free synthesis of free-standing， crystalline， and optoelectronically active nanosheets from small molecules remains elusive. 展開
2010-03-06 01:33:12
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- 幫忙翻譯 化工文獻(xiàn) 在線等 拒絕使用自動翻譯
- Nano-sized Beta zeolites， with a crystal size of 80–100 nm， were synthesized via surface wet method. The nano-sized Hbeta zeolites exhibit much higher activity and stability in the Friedel–Crafts acylation of anisole and toluene with acet... Nano-sized Beta zeolites， with a crystal size of 80–100 nm， were synthesized via surface wet method. The nano-sized Hbeta zeolites exhibit much higher activity and stability in the Friedel–Crafts acylation of anisole and toluene with acetic anhydride than theconventional zeolites of largeparticle size.The smallcrystalsize of nano-sized zeolitesmay bringon more accessible activesites and then enhance the catalytic activity. The exposed pore openings in nano-sized zeolites allow a fast desorption of heavy products from the catalyst and can then reduce the occupancy of active sites by the adsorption of products ，this can then alleviate the catalyst deactivation and improve the catalyst stability deactivation and improve the catalyst stability. 急用 在線等 拒絕用自動翻譯 因?yàn)檫@個(gè)誰都會 如果有超級好用的自動在線翻譯或軟件也可以推薦 展開
2009-05-31 04:30:04
457
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- 請問你能找到關(guān)于蛋白質(zhì)純化與分離的英文文獻(xiàn)及翻譯么
2015-01-04 20:46:08
553
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