求翻譯文獻(xiàn)
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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
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- 白皙孤獨思 2009-12-16 00:00:00
- 陰離子是普遍存在于環(huán)境和生物 系統(tǒng)。例如，氟，廣泛應(yīng)用于牙科 護(hù)理應(yīng)用和展覽某些酶YZ functions.1除了發(fā)揮ZX作用的生物 規(guī)管，氯化也是一個重要的地下水污染 能腐蝕鋼和concrete.2甲狀腺激素 在很大程度上決定碘合成醋酸是一種content.3 可能示蹤的惡性腫瘤，并已被廣泛 調(diào)查的前列腺癌及其metastases.4磷酸鹽 離子是生物和環(huán)境significant.5氰化物 施加對人體健康產(chǎn)生不利影響以及環(huán)境 低濃度。負(fù)離子濃度測定 因此，在許多方面主要關(guān)注的，包括食品 加工，工業(yè)和診所analysis.6然而，親水 例如F陰離子，和氯離子，構(gòu)成強烈氫 債券與質(zhì)子溶劑。因此，發(fā)展熒光 靜電相互作用的基礎(chǔ)上運作的陰離子探針 在極性質(zhì)子溶劑，既是挑戰(zhàn)，目前 不可行。陰離子是普遍存在于環(huán)境和生物 系統(tǒng)。例如，氟，廣泛應(yīng)用于牙科 護(hù)理應(yīng)用和展覽某些酶YZ functions.1除了發(fā)揮ZX作用的生物 規(guī)管，氯化也是一個重要的地下水污染 能腐蝕鋼和concrete.2甲狀腺激素 在很大程度上決定碘合成醋酸是一種content.3 可能示蹤的惡性腫瘤，并已被廣泛 調(diào)查的前列腺癌及其metastases.4磷酸鹽 離子是生物和環(huán)境significant.5氰化物 施加對人體健康產(chǎn)生不利影響以及環(huán)境 低濃度。負(fù)離子濃度測定 因此，在許多方面主要關(guān)注的，包括食品 加工，工業(yè)和診所analysis.6然而，親水 例如F陰離子，和氯離子，構(gòu)成強烈氫 債券與質(zhì)子溶劑。因此，發(fā)展熒光 靜電相互作用的基礎(chǔ)上運作的陰離子探針 在極性質(zhì)子溶劑，既是挑戰(zhàn)，目前 不可行。
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- wxy7812 2009-12-16 00:00:00
- 系統(tǒng)。例如，氟，廣泛應(yīng)用于牙科 護(hù)理應(yīng)用和展覽某些酶YZ functions.1除了發(fā)揮ZX作用的生物 規(guī)管，氯化也是一個重要的地下水污染 能腐蝕鋼和concrete.2甲狀腺激素 在很大程度上決定碘合成醋酸是一種content.3 可能示蹤的惡性腫瘤，并已被廣泛 調(diào)查的前列腺癌及其metastases.4磷酸鹽 離子是生物和環(huán)境significant.5氰化物 施加對人體健康產(chǎn)生不利影響以及環(huán)境 低濃度。負(fù)離子濃度測定 因此，在許多方面主要關(guān)注的，包括食品 加工，工業(yè)和診所analysis.6然而，親水 例如F陰離子，和氯離子，構(gòu)成強烈氫 債券與質(zhì)子溶劑。因此，發(fā)展熒光 靜電相互作用的基礎(chǔ)上運作的陰離子探針 在極性質(zhì)子溶劑，還在研究，目前 不可行。
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- 小女學(xué)畫 2009-12-16 00:00:00
- 陰離子普遍存在于環(huán)境和生物系統(tǒng)中。比如，氟化物廣泛應(yīng)用于牙齒保健，并YZ某些酶的功能。1.除了在生物調(diào)節(jié)中起到關(guān)鍵作用外，氯化物還是地下水的重要污染源，能夠腐蝕鋼筋和混凝土。2.甲狀腺激素合成在很大程度上決定了碘含量。3.醋酸鹽是惡性腫瘤的一種可能的顯示劑，在前列腺癌及其轉(zhuǎn)移的作用已經(jīng)被廣泛研究。4.磷酸鹽離子在生物和環(huán)境方面具有重要意義。5.低濃度的氰化物對人體健康和環(huán)境都會產(chǎn)生損害效應(yīng)。因此在包括食品加工、工業(yè)和臨床診斷等在內(nèi)的眾多領(lǐng)域中，測定陰離子的濃度時主要課題。6.然而，親水離子，比如F-和Cl-，和質(zhì)子溶劑形成高強度的氫鍵。因此，為了在極性質(zhì)子溶劑中讓陰離子發(fā)揮作用而開發(fā)以靜電相互作用為基礎(chǔ)的熒光探測劑不僅挑戰(zhàn)性極大，而且目前也不可行。
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- jiaojunjiaojun 2009-12-16 00:00:00
- 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. 陰離子是普遍存在于環(huán)境和生物 系統(tǒng)。例如，氟，廣泛應(yīng)用于牙科 護(hù)理應(yīng)用和展覽某些酶YZ functions.1除了發(fā)揮ZX作用的生物 規(guī)管，氯化也是一個重要的地下水污染 能腐蝕鋼和concre.2甲狀腺激素 在很大程度上決定碘合成醋酸是一種content.3 可能示蹤的惡性腫瘤，并已被廣泛 調(diào)查的前列腺癌及其metastases.4磷酸鹽 離子是生物和環(huán)境significant.5氰化物 施加對人體健康產(chǎn)生不利影響以及環(huán)境 低濃度。負(fù)離子濃度測定 因此，在許多方面主要關(guān)注的，包括食品 加工，工業(yè)和診所analysis.6然而，親水 例如F陰離子，和氯離子，構(gòu)成強烈氫 債券與質(zhì)子溶劑。因此，發(fā)展熒光 靜電相互作用的基礎(chǔ)上運作的陰離子探針 在極性質(zhì)子溶劑，既是挑戰(zhàn)，目前 不可行。
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- 阿水的 2009-12-16 00:00:00
- 如下： 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. 陰離子在自然環(huán)境和生物體中普遍存。例如，氟元素廣泛應(yīng)用于牙齒保健并表現(xiàn)出YZ某些酶的特征。 1 In addition to playing a central role in biological regulation， chloride is also a major groundwater contaminant that can corrode steel and concrete. 氯元素在生物體中具有重要作用，也是地下水主要污染物之一，并且腐蝕鋼鐵。 2 Thyroid hormone synthesis largely determines iodine content. 甲狀腺激素在很大程度上決定人體內(nèi)碘含量。 3 Acetate is a possible tracer for malignancies and has been extensively investigated in prostate cancer and its metastases. 醋酸有望用作惡性腫瘤的示蹤藥劑。人們對其與前列腺癌的關(guān)系和以及其代謝已展開廣泛研究。 4 Phosphate ion is biologically and environmentally significant. 磷酸鹽離子在生物和環(huán)境方面具有重要意義。 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. 低濃度氰化物有害人體健康，對環(huán)境也不利。負(fù)離子濃度測定在食品加工、工業(yè)和臨床分析中廣受重視。 6 However， hydrophilic anions， such as F- and Cl-， form strong hydrogen bonds with protic solvents. 然而，F(xiàn)- 和 Cl- 等親水陰離子可以與質(zhì)子性溶劑結(jié)合形成鍵能很強的氫鍵。 Therefore， developing fluorescentprobes based on electrostatic interactions for anions functioning in polar protic solvents is both challenging and currently infeasible. 因此，目前研發(fā)基于質(zhì)子性溶劑中靜電相互作用的熒光探針難以實現(xiàn)，并且面臨挑戰(zhàn)。
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- 影云淡風(fēng)輕 2009-12-16 00:00:00
- 陰離子在環(huán)境和生物系統(tǒng)中是常常發(fā)現(xiàn)的。例如，氟化物就廣泛地應(yīng)用于齒科保健應(yīng)用場合，而且能呈現(xiàn)YZ一定的酶的功能。1 除了在生物調(diào)節(jié)方面發(fā)揮核心作用外，氯化物也是一種主要的地下水污染物，它可以腐蝕鋼和混凝土。2 甲狀腺激素的合成很大程度決定了碘的含量。3 醋酸鹽是一種用于惡性腫瘤的可能的示蹤劑，而且在前列腺癌及其轉(zhuǎn)移癌方面已得到廣泛的研究。4 磷酸鹽離子在生物上和環(huán)境上都是很有意義的。5 氰化物在低濃度下就會對人類健康和環(huán)境施加有害的影響。因此決定陰離子的濃度在很多領(lǐng)域都給予了重要關(guān)注，這些領(lǐng)域包括食品加工、工業(yè)和臨床分析。6 然而，親水的陰離子，如F－和Cl－會與質(zhì)子溶劑形成很強的氫鍵。因此，基于活動于極性質(zhì)子溶劑中的陰離子的靜電互作用來研制熒光探測劑就既具有挑戰(zhàn)性，又是目前不可行的。7
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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
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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
448
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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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- 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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- 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
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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
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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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- 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
5
- 求翻譯。。。。。。。。。。。
- During the preparation of the nano-products， these nano-units， such as nanoparticles， nanoclusters， nanowires and nanorods， can also self-assemble into the novel structural aggregates by several routes， including electron irradiation deposi... During the preparation of the nano-products， these nano-units， such as nanoparticles， nanoclusters， nanowires and nanorods， can also self-assemble into the novel structural aggregates by several routes， including electron irradiation deposition [19]， chemical vapor deposition [20]， laser vaporization-condensation [21]， charge transferring [22]， an organic reagent-assisted method [23]， solution-liquid-solid method [24] and catalytic vapor-liquid-solid growth [25]. With these routes， various nanoscale or microscale aggregates can demonstrate novel architectures， including tree-like， web-like， spherical， nanowire-like， network and fishbone-like aggregates. As a well-known method for producing the nanocapsules， however， arc-discharge has been rarely used to synthesize the aggregates self-assembled by the nanocapsules prepared simultaneously in arc-discharge. Nevertheless， it is possible that the arc-discharge can be developed into a new way to synthesize the aggregates. In the present work， we utilized arc-discharge technique with modified strategies， involving changing the hydrogen pressure， introducing gadolinium - aluminum alloy ingot as the anode and adjusting the elements percent of the anode according to their evaporation pressure， to synthesize a new type of nanocapsules， with intermetallic compound GdAl2 as core and amorphous Al2O3 as shell， which enlarge the family of the magnetic nanocapsules. At the same time， the regularly aligned three-dimensional macro-aggregates self-assembled by the nanocapsules without any template and catalyst were simultaneously synthesized in arc-discharge process. 展開
2008-06-09 10:41:10
398
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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 因為這個誰都會 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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- CAN現(xiàn)場總線的英語文獻(xiàn)和翻譯
- 朋友，你可以把你以前的can現(xiàn)場總線的英語論文和翻譯發(fā)給我嗎？60388153@qq.com... 朋友，你可以把你以前的can現(xiàn)場總線的英語論文和翻譯發(fā)給我嗎？60388153@qq.com 展開
2011-04-11 04:11:10
487
2
- 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
1
- 求化學(xué)翻譯
- Graphite powder (<20m)， hydrazine， ammonia， N，Ndimethylformamide (DMF)， dopamine， 0.01M phosphate buffered saline (PBS; 0.138M NaCl， 0.0027M KCl， pH 7.4)， and ascorbic acid were purchased form Aldrich and used as received. Doubly disti... Graphite powder (<20m)， hydrazine， ammonia， N，Ndimethylformamide (DMF)， dopamine， 0.01M phosphate buffered saline (PBS; 0.138M NaCl， 0.0027M KCl， pH 7.4)， and ascorbic acid were purchased form Aldrich and used as received. Doubly distilled water was used throughout the whole experiments. The data of cyclic voltammetry (CV)， differential pulse voltammetry (DPV)， and electrochemical impedance spectra were obtained with a CHI 660 electrochemical workstation (CH instruments， Austin， TX). The electrochemical cell consisted of GCE (3mm diameter， Bioanalytical Systems， Inc.) as working electrode， Ag/AgCl (Bioanalytical Systems， Inc.) as reference electrode， and platinum wire as counter electrode. The impedance data were fitted to an appropriate equivalent circuit using ZsimpWin 3.0 software (Echem Software). The Raman spectra of graphene were obtained by micro-Raman system equipped with a homemade sample stage， a monochromator (SPEX 500 M)， and a CCD camera (Roger Scientific model 7346-001) with 514.5nm wavelength laser line. Graphene was characterized by field emission scanning electron microscope (SUPRA 55VP， Carl Zeiss) and atomic force microscope (NanostationII， Surface Imaging Systems). 展開
2012-03-12 11:00:58
425
2
- 求韓語翻譯
- 3? ??然 ?? ?? ???? ? ?? ???? ??? ?? ??? ?? &... 3? ??然 ?? ?? ???? ? ?? ???? ??? ?? ??? ?? ??? ?? ??? ?? ????、 求準(zhǔn)確翻譯 PS 3元催化劑是安裝在汽車排氣管上的 展開
2012-12-19 08:48:48
448
1
- 繼續(xù)求翻譯
- Ethylacetate(Quimis，p.a.)，methanol(Quimis，p.a.)，sec-butanol(Merck，HPLCgrade)，oleicacid(Merck，extrapure)，hydrogenperoxide(Interox，70%，w/waqueoussolution)，aluminumoxideforc... Ethyl acetate (Quimis， p.a.)， methanol (Quimis， p.a.)， sec- butanol (Merck， HPLC grade)， oleic acid (Merck， extra pure)， hydrogen peroxide (Interox， 70%， w/w aqueous solution)， aluminum oxide for chromatography (Fluka， 0.05–0.15 mm)， aluminum oxide for column chromatography (Acros Organics， activated， acidic， 0.1–0.5 mm)， aluminum tri-sec-butoxide (Aldrich， 99.99%)， oxalic acid (Synth， p.a.)， di-n-butyl ether (Fluka， >99%) and soybean oil (Cargill) were used as received. The solution of anhydrous hydrogen peroxide (24%， w/w) in ethyl acetate was prepared from aqueous H2O2 (70%， w/w) in ethyl acetate by azeotropic distillation with a Dean-Stark apparatus [14] The products were identified by gas chromatography–mass spectroscopy (GC–MS) using a Hewlett-Packard 5890 gas chromatograph equipped with a AT-Wax column and interfaced with a Hewlett-Packard 5971A mass spectrometer. Helium was used as the carrier gas. A similarly equipped Hewlett-Packard5890 gas chromatograph using nitrogen as the carrier gas and a flame ionization detector was used for product quantification， with the help of calibration curves. 展開
2009-03-18 10:12:57
457
3
- 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
449
2
- 高分求高手翻譯，不要機械翻譯
- Bimetallic dendrimer-encapsulated nanoparticles(DENs)are important materials，because they have demonstrated improvement in performance compared to the monometallic DENs in many systems when they are used as catalysts.This tutorial review fo... Bimetallic dendrimer-encapsulated nanoparticles(DENs)are important materials，because they have demonstrated improvement in performance compared to the monometallic DENs in many systems when they are used as catalysts.This tutorial review focuses on the recent research advances in bimetallic DENs with respect to their synthesis，characterization，and applications as catalysts.Bimetallic DENs can be made mainly via three routes:co-complexation，sequential loading，and partial displacement.The research in bimetallic DENs has been significantly promoted by the advancement of characterization instruments.The performances of bimetallic DENs as homogeneous and heterogeneous catalysts in organic synthesis have been compared with both monometallic DENs and their physical mixtures.It is concluded that the synergistic electronic effect in bimetallic nanoparticles enhances their catalytic activities. 能翻譯多少都可以的 展開
2009-03-24 13:04:22
368
2
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