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| 1 | 三维多站测向交叉定位算法及精度分析显示文摘在多站的测向交叉定位中,常把三维问题分解成二维和一维分别解算,这种方法虽简单易行,但定位精度有待进一步的提高。文中详细推算了这种算法的误差模型;然后给出一种用泰勒级数法结合最小二乘的思想进行定位的方法,并通过仿真计算证明了这种泰勒级数法的定位性能要优于前者。 | 李洪梅 陈培龙 | 2007 | 指挥控制与仿真2007，29，2： | 23 |
| 2 | 白酒中挥发性苦涩味物质的提取和分离显示文摘为鉴定白酒中挥发性苦味和涩味化合物,建立了一种新的提取和分离白酒中苦味和涩味物质的方法。通过梯度减压蒸馏将白酒样品分成4个组分(A、B、C和D),具有强烈苦味和涩味的组分B通过半制备液相再分离,得到10个亚组分,每个亚组分分别用戊烷和乙醚萃取,收集乙醚萃取相。将每一个乙醚相平均分成两份,一份用纯净水洗涤,水洗相用真空旋转蒸发除去溶剂,用于味觉稀释分析(taste dilution analysis,TDA);另一份氮吹浓缩至250μL进行GC-MS分析。TDA结果表明,4个乙醚萃取组分B-8-Ⅱ、B-2-Ⅱ、B-3-Ⅱ和B-4-Ⅱ具有较高的TD值,其涩味TD值分别为128、64、32和8,苦味TD值分别为32、16、16和8。通过GC-MS共鉴定出7种呈味化合物,经标准品验证,2-苯乙醇和乳酸乙酯呈现涩味;糠醛、2-甲基丙醇、3-甲基丁醇、1-丁醇和正丙醇呈涩味和苦味,其中,2-苯乙醇的味觉特征是首次报道。 | 王尹叶 范文来 徐岩 | 2018 | 食品与发酵工业2018，44，6： | 15 |
| 3 | Determination of 50% endpoint titer using a simple formula显示文摘Two commonly used methods for calculating 50% endpoint using serial dilutions are Spearman-Karber method and Reed and Muench method. To understand/apply the above formulas, moderate statistical/mathematical skills are necessary. In this paper, a simple formula/method for calculating 50% endpoints has been proposed. The formula yields essentially similar results as those of the SpearmanKarber method. The formula has been rigorously evaluated with several samples. | Muthannan Andavar Ramakrishnan | 2016 | World Journal of Virology2016，5，2： | 12 |
| 4 | An analysis of the wide area differential method of geostationary orbit satellites显示文摘This work aims to obtain a wide area differential method for geostationary orbit (GEO) constellation. A comparison between the dilution of precision (DOP) of four-dimensional (4D) calculation including sa- tellite clock errors and ephemeris errors and that of three-dimensional (3D) calculation only including ephemeris errors with the inverse positioning theory of GPS shows the conclusion that all the 3D PDOPs are greatly reduced. Based on this, a basic idea of correcting satellite clock errors and ephem- eris errors apart is put forward, and moreover, a specific method of separation is proposed. Satellite clock errors are separated in a master station with time synchronization, and all the remaining pseu- do-range errors after the satellite clock errors have been deducted are used to work out ephemeris corrections of all GEO satellites. By a comparative analysis of user positioning accuracy before and after differential, the wide area differential method is verified to be quite valid for GEO constellation. | CAI ChengLin1,2,3?, LI XiaoHui1 & WU HaiTao1 1 National Time Service Center, Chinese Academy of Sciences, Lintong 710600, China 2 Hunan Institute of Humanities, Science and Technology, Loudi 417000, China 3 Graduate University of Chinese Academy of Sciences, Beijing 100049, China | 2009 | Science China(Physics,Mechanics & Astronomy)2009，52，2： | 7 |
| 5 | A Study of the Rhenium-Osmium Geochronometry of Molybdenites显示文摘This study deals with the first application of the isotope dilution - inductively coupled plasma mass spectrometry in the rhenium-osmium geochronometry in China. The chemical separation procedure included decomposition of samples by means of alkali fusion, extraction of rhenium by acetone and extraction of osmium by distillation. The recovery of both elements in the entire process was more than 90% . The blanks of analyses were 0.07 ng for rhenium and 0.01 ng for 187Os. The mineralization ages of molybdenites from four molybdenum deposits in China were determined by using this method, with a precision (2σ)of about ±3% . These results agree satisfactorily with their geological backgrounds. The Re-Os method can directly determine ages of metal deposits and reflect the true ages more reliably than other dating methods that only determine the ages of country rocks from which mineralization ages are inferred. As many hydrothermal sulphide deposits usually contain molybdenites, this method has bright | Du Andao, He Hongliao, Yin Ningwan, Zou Xiaoqiu,Sun Yali, Sun Dezhong, Chen Shaozhen and Qu Wenjun Institute of Rock and Mineral Analysis, Chinese Academy of Geological Sciences, Beijing Fei Zhenbi | 1995 | Acta Geologica Sinica(English Edition)1995，69，2： | 7 |
| 6 | Experimental study of Iranian heavy crude oil viscosity reduction by diluting with heptane, methanol, toluene, gas condensate and naphtha显示文摘Due to the high viscosity of heavy crude oils,production from these reservoirs is a demanding task.To tackle this problem,reducing oil viscosity is a promising approach.There are various methods to reduce viscosity of heavy oil:heating,diluting,emulsification,and core annular flow.In this study,dilution approach was employed,using industrial solvents and gas condensate.The viscosity of two Iranian heavy crude oils was measured by mixing with solvents at different temperatures.Dilution of both oil samples with toluene and heptane,resulted in viscosity reduction.However,their effect became less significant at higher concentrations of diluent.Because of forming hydrogen bonds,adding methanol to heavy crude oil resulted in higher viscosity.By adding condensate,viscosity of each sample reduced.Gas condensate had a greater impact on heavier oil;however,at higher temperatures its effect was reduced.Diluting with naphtha decreased heavy oil viscosity in the same way as n-heptane and toluene.Besides experimental investigation,different viscosity models were evaluated for prediction of heavy oil/solvent viscosity.It was recognized that Lederer'model is the best one. | Amir Hossein Saeedi Dehaghani Mohammad Hasan Badizad | 2016 | Petroleum2016，2，4： | 6 |
| 7 | THREE-DIMENSIONAL NUMERICAL SIMULATION OF MUL-TIPLE JETS IN SHALLOW FLOWING RECEIVING WATERS显示文摘This paper is concerned with the simulation of the mixing mechanism of submerged multiport diffusers us ed to discharge heated water from thermal-electric power plants and households into shallow receiving waters. The three-dimensional turbulence model and hybri d finite analytic method are used to predict the behavior of near field for mult iport buoyant jets in rivers. The predicted temperature dilution and velocity pr ove good by comparison with available laboratory measurements. An empirical form ula for temperature dilution and velocity in near field for this kind of flow is given. The effect of parameters on the dilution behavior of multiple jets are a lso discussed. | Huai, Wenxin | 2000 | Journal of Hydrodynamics2000，12，3： | 5 |
| 8 | Estimating total nitrogen deposition in agroecosystems in northern China during the wheat cropping season显示文摘Atmospheric nitrogen (N) deposition has been poorly documented in northern China, an intensive agricultural and industrial region with large emissions of NHx and NOy. To quantify N deposition, total airborne N deposition was determined at three agricultural sites using a manual integrated total nitrogen input (ITNI) system during growth of winter wheat (Triticum aestivum L.) and Italian ryegrass (Lolium multiflorum Lam.) from September 2005 to May 2006. Total estimated N deposition averaged 54.9 and 43.2 kg N/hm2 across the three sites when wheat was grown to flowering and maturing, respectively. The average value was 50.2 kg N/hm2 when ryegrass was the indicator plant. Both indicator species gave similar total airborne N input results. The intermediate level of N supplied resulted in the highest N deposition, and the ratio of N acquired from deposition to total N content of the whole system decreased with increasing N supply to the roots. The contribution of atmospheric N to the total N content of the wheat and ryegrass sand culture systems ranged from 10% to 24%. | Christie PETER Fangmeier ANDREAS | 2010 | Journal of Arid Land2010，2，1： | 5 |
| 9 | 高效液相色谱法-同位素稀释质谱联用法对奶粉中维生素A含量的检测显示文摘A method for the determination of vitamin A in milk powder was developed by high performance liquid chromatography-isotope dilution mass spectrometry(HPLC-ID MS) and using deuterium-labeled vitamin A as an internal standard.RSD of the method was 2.85%.This method was applied in the determination of standard reference material SRM 1849 with satisfactory results. | 黄挺 张伟 刘军 田颖 杨改霞 | 2008 | 分析测试学报2008，27，S1： | 5 |
| 10 | 基于最优几何的改进型多星座卫星选星算法显示文摘随着多星座卫星导航技术的发展,卫星选星算法也日趋重要。为了保证导航定位解算的实时处理能力,在所有可见卫星中合理选取部分卫星用于定位解算,是十分必要的。本文提出了一种基于最优几何分布的改进型选星算法,能够选取多于四颗的卫星用于定位,且卫星几何分布近似最优。算法基于最优几何分布,并利用了模糊综合评判来降低GDOP值的计算次数,减少接收机计算负担。仿真结果表明,改进型选星算法较最优几何分布选星算法在GDOP值上增大不多,而GDOP值的计算次数却能显著地降低,因此提升了接收机实时处理能力。 | 陈杨毅 陈凌宇 | 2014 | 软件2014，35，1： | 5 |
| 11 | 液相色谱同位素稀释质谱对寡核苷酸含量的测定研究显示文摘The mass of oligonucleotides was quantitated by liquid chromatography-isotope dilution mass spectrometry.The uncertainty was calculated.This could provide information for the further quantitative measurement and utilization of DNA. | 高运华 武利庆 王晶 张玲 刘张岚 | 2008 | 分析测试学报2008，27，S1： | 4 |
| 12 | In-vitro antimicrobial activity screening of some ethnoveterinary medicinal plants traditionally used against mastitis,wound and gastrointestinal tract complication in Tigray Region,Ethiopia显示文摘Objective:To screen the antibacterial activity of nine ethnoveterinary plants traditionally used for the treatment of mastitis,wound and gastrointestinal complications.Methods:Hydroalcoholic exctracts of medicinal plants namely,Achyranthes aspera(A.aspera) L.(Family Asparagaceae),Ficus caria(F.caria)(Family Moraceae).Malvi parviflora(M.parviflora)(Family Malvaceae),Vernonia species(V.species) docal name Alakit.Family Asteraceae),Solatium hastifolium(S.hastifolium)(Family Solanaceae),Calpurinia aurea(C.aurea)(Ait) Benth(Family Fabaceae),Nicotiana tabacum(N.tabacum) L.(Family Solanaceae),Ziziphus spina-christi(Z.spina-christi)(Family Rhamnaceae).Croton macroslachys(C.macrostachys)(Family Fuphorhiaceae).were screened against clinical bacterial isolates of veterinary importance from October 2007 to April2009.The antibacterial activity was tested using disc diffusion at two concentrations(200 mg/mL and 100 mg/mL) and broth dilution methods using 70%methanol macerated leal extracts.Results:With the exception ol S.hastifolium all plant extracts exhibited antibacterial activity.Among the medicinal plants tested C.aurea.C.macrostachyus,A.aspera,N.tabacum and vcrnonia species(Alakit) showed the most promising antimicrobial properties.Conclusions:It can be concluded that many of the tested plants have antibacterial activity and supports the traditional usage of the plants for mastitis,wound and gastrointestinal complications treatment.Further studies into their toxicity and phytochemistry is advocated. | Shewit Kalayou Mekonnen Haileselassie Gebremedhin Gebre-egziabher Tsegay Tiku'e Samson Sahle Habtamu Taddele Mussie Ghezu | 2012 | Asian Pacific Journal of Tropical Biomedicine2012，2，7： | 3 |
| 13 | From statistical analysis to process optimization during cladding using a Nd:YAG laser显示文摘Application of statistical methods to optimize the process parameters was achieved by employing full factorial design of experiments,which was accomplished by cladding using stepwise ramped laser power.The correlations between clad geometry and dilution(clad characteristics)and the main process parameters laser power(P_(l)),cladding speed(v_(c)),the powder feed rate(m)were obtained through application of variance analysis technique(ANOVA).The obtained correlations between the main processing parameters and the clad characteristics are discussed and a statistical model was developed.The desirability investigations using the developed statistical model were performed by considering the clad geometry,aspect ratio,dilution and hardness.Optimal parameters for cladding Stellite 6 on AISI 420 steel substrate and for cladding Nucalloy 488V on S355 J2 steel substrate were obtained.The optimal processing parameters can be applied to clad other materials with similar chemical compositions. | 亚伟 Pathiraj B. 于兴华 | 2022 | China Welding2022，31，4： | 2 |
| 14 | 同位素稀释-ICPMS法测定地质标准物质中铂族元素显示文摘Platinum group elements (PGEs) includes platinum, palladium, iridium, osmium, rhodium and ruthenium. It has very high economic and scientific value in the field of geoscience and environmental science. But the analysis data referred by the different lab are very disperse because of the difficulty of the determination of PGEs. It makes very difficult to fix the value of the PGEs in the standard reference materials. In the article, the values of the PGEs in the standard reference materials of ocean sediment are determined by isotope dilution technique and dependable values of these elements are provided. | 胡明月 何红蓼 | 2005 | 质谱学报2005，26，z1： | 2 |
| 15 | 同位素稀释质谱法对溶液中血管紧张素Ⅰ含量的测定显示文摘The presented work is to determine the mass fraction of angiotensinⅠ in solution by isotope dilution method,which is a pilot study organized by Consultative Committee for Amount of Substance.Firstly,the hydrolysis time and hydrochloric acid addition volume ratio were optimized and the degradation of natural and isotope labeled proline,valine,leucine and phenylalanine during the hydrolysis process were investigated.Secondly,the mass fractions of proline,valine,isoleucine and phenylalanine in the angiotensinⅠhydrolysis solution was determined employing isotope dilution method with their reference materials as standards.Finally,the angiotensinⅠ mass fraction and associated uncertainty were calculated according to the amino acid mass fraction obtained,which was(75.2±2.6) μg/g.It showed that the result obtained in this paper has good equivalence with the average.It can be concluded that the isotope dilution method for peptide quantification is accurate and is suitable for peptide reference materials production. | 武利庆 王晶 张玲 盛灵慧 杨彬 黎朋 | 2008 | 分析测试学报2008，27，S1： | 2 |
| 16 | Evaluation of berries of Phytolacca dodecandra for growth inhibition of Histoplasma capsulatum var.farciminosum and treatment of cases of epizootic lymphangitis in Ethiopia显示文摘Objective:To evaluate the berries of Phytolacca dodecundra(P.dodecandra) for its effect on Histoplasma cupsulatum var.farciminosum(HCF) and for the treatment of cases of epizootic lymphangitis(ELi.Methods:Samples were collected from un-ruptured nodules of cases of EL at Debre Zeit and Akaki(central Ethiopia).Mycologieal culture and isolation of HCF were performed at the Akliln Lemma Institute of Pathobiology.Phytochemical screening was done for n-butanol extract of P.dodecandra to delect alkaloids,saponins,phenolic compounds and flavonoids.The minimum inhibitory concentrations(MICs) and minimum fungicidal concentrations(MFCs) ol aqueous and n-butanol extracts of P.dodecandra against FICF were determined by agar dilution assay.For the in vivo trial.5%simple ointment was prepared from n-butanol extract and applied topically to 24(twelve early and twelve moderate) cases of F.L.Results:Phytochemical screening showed that n-butanol extract ol P.dodecandra was positive lor alkaloids.saponins and phenolic compounds but negative for flavonoids.The MFCs of n-butanol and aqueous extracts of P.dodecandra were(0.039%-0.078%) and(0.625%-1.250%),respectively.The MFCs of n-butanol and aqueous extracts of P.dodecandra were(0.078%t-0.156%)and(1.250%-2.500%),respectively.The MIC and MFC of ketoconazole(positive control) was(1.200×10^(-5)%-2.500×10^(-5)%) and(5.000× 10^(-5)%-1.000×10^(-4)%),respectively while growth was observed on free medium(negative control).From the total of 24 treated cases of EL,14(58.3%) responded lo treatment;however,10(41.7%) did not respond to treatment.There was no significant difference in the degree of response to treatment between early and moderate cases(χ~2=0.086:P=0.408.Conclusions:It can be concluded that n-butanol extract of P.dodecandra demonstrates antifungal effects while the aqueous extract shows no antifungal activity. | Negesse Mekonnen Eyasu Makonnen Nigatu Aklilu Gobena Ameni | 2012 | Asian Pacific Journal of Tropical Biomedicine2012，2，7： | 2 |
| 17 | Numerical study on combustion of diluted methanol-air premixed mixtures显示文摘The effect of nitrogen dilution on the premixed combustion characteristics and flame structure of laminar premixed methanol-air-nitrogen mixtures are analyzed numerically based on an extended methanol oxidation mechanism. The laminar burning velocities, the mass burning fluxes, the adiabatic flame temperature, the global activation temperature, the Zeldovich number, the effective Lewis number and the laminar flame structure of the methanol-air-nitrogen mixtures are obtained under different nitrogen dilution ratios. Comparison between experiments and numerical simulations show that the extended methanol oxidation mechanism can well reproduce the laminar burning velocities for lean and near stoichiometric methanol-air-nitrogen mixtures. The laminar burning velocities and the mass burning fluxes decrease with the increase of nitrogen dilution ratio and the effect is more obvious for the lean mixture. The effective Lewis number of the mixture increases with the increase of nitrogen dilution ratio, and the diffusive-thermal instability of the flame front is decreased by the nitrogen addition. Nitrogen addition can suppress the hydrodynamic instability of methanol-air-nitrogen flames. The decrease of the mole fraction of OH and H is mainly responsible for the suppressed effect of nitrogen diluent on the chemical reaction in the methanol-air-nitrogen laminar premixed flames, and the NOx and formaldehyde emissions are decreased by the nitrogen addition. | Zheng JianJun Zhang ZhiYuan Huang ZuoHua Hu ErJiang Tang ChengLong Wang JinHua | 2010 | Chinese Science Bulletin2010，55，9： | 1 |
| 18 | Direct Dating of Molybdenites Using the Re-Os Geochronometer显示文摘Re-Os geochronometry based on the Os isotopic changes caused by the radioactive de-cay of 187Re to 187Os is ideally suitable for direct dating of some metalliferous deposits.Nevertheless,its applications have been hampered by the analytical difficulties over a longtime.Since the 1980s,the developments of various mass spectrometric techniques,such as secondary ion mass spectrometry(SIMS),inductively coupled plasma massspectrometry(ICPMS),and negative thermal ionisation mass spectrometry(NTIMS),havepromoted the studies on the Re-Os chronometry.This work applied isotope dilution-ICPMSto the analysis of Re and Os for the purpose of direct dating of molybdenites.Afterdecomposing the sample with alkali fusion,Re was separated by extraction and Os | 杜安道 殷宁万 孙亚利 陈少珍 何红蓼 邹晓秋 孙德忠 屈文俊 | 1993 | Chinese Science Bulletin1993，38，15： | 1 |
| 19 | Comparative study on production,purification of penicillin by Penicillium chrysogenum isolated from soil and citrus samples显示文摘Objective:To explore various unexplored locations where Penicillium spp.would be available and study the production of penicillin from the isolated Penicillium spp.in different media with altered carbohydrate source.Methods:The collected soil samples were screened for the isolation of Penicillium chrysogenum(P.chrysogenum) by soil dilution plate.The isolated Penicillium species were further grown in different production media with changes in the carbohydrate source.The extracted penicillin from various isolates was analyzed by HPLC for the efficacy of the product.Further the products were screened with various bacterial species including methicillin resistant Staphylococcus aureus(MRSA).And the work was extended to find the possible action on MRSA,along with characterization using other pathogens.Results:From the various soil and citrus samples used for analysis,only the soil sample from Government General Hospital of Bangalore,India,and Sanjay Gandhi Hospital,Bangalore,India,showed some potential growth of the desired fungi P.chrysogenum.Different production media showed varied range of growth of PenicilUum.Optimum production of penicillin was obtained in maltose which proved maximum zone of inhibition during assay.Characterization of penicillin on pathogens,like wild Escherichia coli strain,Klebsiella spp.,and MRSA,gave quite interesting results such as no activity on the later strain as it is resistant.HPLC data provided the analytical and confirmation details of the penicillin produced.Accordingly,the penicillin produced from the soil sample of Government General Hospital had the high milli absorbance unit of 441.5 mAu compared with that of the penicillin produced from Sanjay Gandhi Hospital sample,8S.S2 mAu.Therefore,there was a considerable change in quantity of the penicillin produced from both the samples.Conclusions: The Penicillium spp.could be possibly rich in hospital contaminants and its environments.This research focuses on various unexplored sources of medical ailments,and also shows that the growth of penicillin is high in maltose rich media that could possibly enhance the growth. | S Anto Jeya Dayalan Pramod Darwin Prakash S | 2011 | Asian Pacific Journal of Tropical Biomedicine2011，1，1： | 1 |
| 20 | Performance improvement of n-i-p μc-Si:H solar cells by gradient hydrogen dilution technique显示文摘High pressure radio frequency plasma enhanced chemical vapor deposition(RF-PECVD)process was adopted to investigate the effect of constant hydrogen dilution technique and gradient hydrogen dilu-tion technique on the structural evolution of intrinsic films and the performance of n-i-p microcrystal-line silicon solar cells.The experiment results demonstrated that the grain size and crystalline volume fraction along the growth direction of intrinsic films can be controlled and the performance of solar cells can be greatly improved by gradient hydrogen dilution technique.An initial active-area efficiency of 5.7%(Voc=0.47V,Jsc=20.2mA/cm2,FF=60%)for the μc-Si:H single-junction n-i-p solar cells and an initial active-area efficiency of 10.12%(Voc=1.2V,Jsc=12.05mA/cm2,FF=70%)for the a-Si:H/μc-Si:H tandem n-i-p solar cells has been achieved. | YUAN YuJie HOU GuoFu ZHANG JianJun XUE JunMing CAO LiRan ZHAO Ying GENG XinHua | 2009 | Science China(Technological Sciences)2009，52，6： | 1 |
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