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| 1 | Hf isotopes of the 3.8 Ga zircons in eastern Hebei Province, China: Implications for early crustal evolution of the North China Craton显示文摘Zircon U-Pb dating indicates that the fuchsite quartzite in eastern Hebei Province was derived from weathering and erosion of the 3.6-3.8 Ga granitic rocks. In-situ zircon Hf analyses show that the Lu-Hf isotopic system remained closed during later thermal disturbances. Zircons with concordant ages have Hf isotopic model ages of about 3.8 Ga, suggesting a recycling of this ancient crust. The ~3.8 Ga zircons have similar Hf isotopic compositions to those of chondrite, indicating that their source rocks (granitic rocks) were derived from partial melting of the juvenile crust which originated from a mantle without significant crust-mantle differentiation. Therefore, it is proposed that there was no large-scale crustal growth before ~3.8 Ga in eastern Hebei Province. Considering zircon Hf isotopic data from other areas, it is concluded that the most ancient crust in the North China Craton probably formed at about 4.0 Ga, and the possibility to find crust older than 4.0 Ga is very limited. | WU Fuyuan YANG Jinhui LIU Xiaoming LI Tiesheng XIE Liewen YANG Yueheng | 2005 | Chinese Science Bulletin2005，50，21： | 51 |
| 2 | Advanced prediction of tunnel boring machine performance based on big data显示文摘Predicting the performance of a tunneling boring machine is vitally important to avoid any possible accidents during tunneling boring.The prediction is not straightforward due to the uncertain geological conditions and the complex rock-machine interactions.Based on the big data obtained from the 72.1 km long tunnel in the Yin-Song Diversion Project in China,this study developed a machine learning model to predict the TBM performance in a real-time manner.The total thrust and the cutterhead torque during a stable period in a boring cycle was predicted in advance by using the machine-returned parameters in the rising period.A long short-term memory model was developed and its accuracy was evaluated.The results show that the variation in the total thrust and cutterhead torque with various geological conditions can be well reflected by the proposed model.This real-time predication shows superior performance than the classical theoretical model in which only a single value can be obtained based on the single measurement of the rock properties.To improve the accuracy of the model a filtering process was proposed.Results indicate that filtering the unnecessary parameters can enhance both the accuracy and the computational efficiency.Finally,the data deficiency was discussed by assuming a parameter was missing.It is found that the missing of a key parameter can significantly reduce the accuracy of the model,while the supplement of a parameter that highly-correlated with the missing one can improve the prediction. | Jinhui Li Pengxi Li Dong Guo Xu Li Zuyu Chen | 2021 | Geoscience Frontiers2021，12，1： | 17 |
| 3 | In situ U-Pb dating of titanite by LA-ICPMS显示文摘Titanite is an ideal mineral for U-Pb isotopic dating because of its relatively high U,Th and Pb contents.Here,we developed a technique for U-Pb dating of titanite using the 193 nm ArF laser-ablation system and Agilent 7500a Q-ICP-MS.Standards of titanite (BLR-1 and OLT-1) and zircon (91500 and GJ-1) were dated using single spot and line raster scan analytical methods.To check the matrix effect,titanite (BLR-1) and zircon (91500) standards were analyzed as the external standards.The weighted mean 206 Pb/238 U ages of OLT-1 titanite are 1015±5 Ma (2,n=24) and 1017±6 Ma (2,n=24) by single spot and line raster scan analyses,respectively,using BLR-1 titanite as the external standard.These ages are consistent with its reference age of about 1014 Ma.However,using 91500 zircon as the external standard,the weighted mean 206 Pb/238 U ages are 917±4 Ma (2,n=24) and 927±5 Ma (2,n=24) for BLR-1 titanite,and 891±4 Ma (2,n=24) and 901±5 Ma (2,n=24) for OLT-1 titanite by single spot and line raster scan analyses,respectively.It is evident that these ages are ~12% younger than their reference values.Our results reveal that significant matrix effect does exist between different kinds of minerals during LA-ICPMS U-Pb age determination,whereas it is insignificant between same minerals.Therefore,same mineral must be used as the external standard for fractionation corrections during in situ LA-ICPMS U-Pb age analysis.In addition,we determined U-Pb ages for titanites from the Early Cretaceous Fangshan pluton,which indicates a rapid cooling history of this pluton. | SUN JinFeng YANG JinHui wu FuYuan XIE LieWen YANG YueHeng LIU ZhiChao LI XianHua | 2012 | Chinese Science Bulletin2012，57，20： | 14 |
| 4 | Esophageal cancer:Epidemiology,risk factors and screening显示文摘More than 600,000 people are diagnosed with esophageal cancer(EC)every year globally,and the five-year survival rate of EC is less than 20%.Two common histological subtypes of EC,esophageal squamous cell carcinoma(ESCC)and esophageal adenocarcinoma(EAC),have great geographical variations in incidence rates.About half of the world’s EC was diagnosed in China and a majority of which belong to ESCC.Globally,the overall incidence rate of EC is decreasing.In some high-risk Asian regions,such as China,the incidence rate of ESCC has generally declined,potentially due to economic growth and improvement of diet habits.In some European high-income countries and the United States,the decline is mainly attributed to the decrease in smoking and drinking.The risk factors of EC are not well understood,and the importance of environmental and genetic factors in the pathogenesis is also unclear.The incidence and mortality of advanced EC can be reduced through early diagnosis and screening.White light endoscopy is still the gold standard in the current screening technology.This article reviews the epidemiology,risk factors,and screening strategies of EC in recent years to help researchers determine the most effective management strategies to reduce the risk of EC. | Jiang Li Jianguo Xu Yadi Zheng Ya Gao Siyi He He Li Kaiyong Zou Ni Li Jinhui Tian Wanqing Chen Jie He | 2021 | Chinese Journal of Cancer Research2021，33，5： | 12 |
| 5 | A Resistant Quantum Key Exchange Protocol and Its Corresponding Encryption Scheme显示文摘The emergence of quantum computer will threaten the security of existing public-key cryptosystems,including the Diffie Hellman key exchange protocol,encryption scheme and etc,and it makes the study of resistant quantum cryptography very urgent.This motivate us to design a new key exchange protocol and encryption scheme in this paper.Firstly,some acknowledged mathematical problems was introduced,such as ergodic matrix problem and tensor decomposition problem,the two problems have been proved to NPC hard.From the computational complexity prospective,NPC problems have been considered that there is no polynomial-time quantum algorithm to solve them.From the algebraic structures prospective,non-commutative cryptography has been considered to resist quantum.The matrix and tensor operator we adopted also satisfied with this non-commutative algebraic structures,so they can be used as candidate problems for resisting quantum from perspective of computational complexity theory and algebraic structures.Secondly,a new problem was constructed based on the introduced problems in this paper,then a key exchange protocol and a public key encryption scheme were proposed based on it.Finally the security analysis,efficiency,recommended parameters,performance evaluation and etc.were also been given.The two schemes has the following characteristics,provable security,security bits can be scalable,to achieve high efficiency,quantum resistance,and etc. | MAO Shaowu ZHANG Huanguo WU Wanqing LIU Jinhui LI Shuanbao Wang Houzhen | 2014 | China Communications2014，11，9： | 11 |
| 6 | Spent rechargeable lithium batteries in e-waste: composition and its implications显示文摘电池(RLB ) 在便携式的电子设备和电的车辆由于这些电池的宽申请很快正在种的花的可充电的锂的数量,它强迫那花的 RLB 应该适当地被处理。花的 RLB 的鉴定能为再循环的花的 RLB 供应基本信息。这研究试图在各种各样的花的 RLB 之中决定物理部件和化学作文的差别。RLB 的所有采样被引入的联合血浆严厉地拆除并且测量原子排放分光计。结果显示隔板,阳极和阴极的全部的重量的一般水准占了超过 60% 所有 RLB。珍贵金属的重量比率从 26% ~ 76% ,和约 20% 全部的重量是 Cu 和艾尔。而且,没有重要差别在不同制造商,应用,和电解质类型之中被发现。并且考虑便携式的电子设备,也在在 RLB 的沥滤的液体的 Co-Li 集中比率没有重要差别。 | Xianlai ZENG Jinhui LI | 2014 | Frontiers of Environmental Science & Engineering2014，8，5： | 10 |
| 7 | Movable electrowetting optofluidic lens for optical axial scanning in microscopy显示文摘Optical axial scanning is essential process to obtain 3D information of biological specimens. To realize optical axial scanning without moving, the tunable lens is a solution. However, the conventional tunable lenses usually induce non-uniform magnification and resolution issues. In this paper, we report a movable electrowetting optofluidic lens. Unlike the conventional tunable lens, our proposed optofluidic lens has two liquid-liquid (L-L) interfaces, which can move in the cell by an external voltage. The object distance and image distance are adjusted by shifting the L-L interface position. Therefore, the proposed lens can realize optical axial scanning with uniform magnification and resolution in microscopy. To prove the concept, we fabricate an optofluidic lens and use it in optical axial scanning. The scanning distance is more than 1 mm with uniform magnification and good imaging quality. Widespread application of such a new adaptive zoom lens is foreseeable. | Lei Li Liang Xiao Jinhui Wang Qionghua Wang | 2019 | Opto-Electronic Advances2019，2，2： | 8 |
| 8 | Landslide identification using machine learning显示文摘Landslide identification is critical for risk assessment and mitigation.This paper proposes a novel machinelearning and deep-learning method to identify natural-terrain landslides using integrated geodatabases.First,landslide-related data are compiled,including topographic data,geological data and rainfall-related data.Then,three integrated geodatabases are established;namely,Recent Landslide Database(Rec LD),Relict Landslide Database(Rel LD)and Joint Landslide Database(JLD).After that,five machine learning and deep learning algorithms,including logistic regression(LR),support vector machine(SVM),random forest(RF),boosting methods and convolutional neural network(CNN),are utilized and evaluated on each database.A case study in Lantau,Hong Kong,is conducted to demonstrate the application of the proposed method.From the results of the case study,CNN achieves an identification accuracy of 92.5%on Rec LD,and outperforms other algorithms due to its strengths in feature extraction and multi dimensional data processing.Boosting methods come second in terms of accuracy,followed by RF,LR and SVM.By using machine learning and deep learning techniques,the proposed landslide identification method shows outstanding robustness and great potential in tackling the landslide identification problem. | Haojie Wang Limin Zhang Kesheng Yin Hongyu Luo Jinhui Li | 2021 | Geoscience Frontiers2021，12，1： | 8 |
| 9 | An investigation on micro pore structures and the vapor pressure mechanism of explosive spalling of RPC exposed to high temperature显示文摘Reactive powder concrete(RPC) is vulnerable to explosive spalling when exposed to high temperature.The characteristics of micro pore structure and vapor pressure of RPC are closely related to the thermal spalling.Applying mercury intrusion porosimetry(MIP) and scanning electron microscopy(SEM) techniques,the authors probed the characteristics of micro pore structures of plain RPC200 when heated from 20-350℃.The pore characteristics such as specific pore volume,threshold pore size and most probable pore size varying with temperatures were investigated.A vapor pressure kit was developed to measure the vapor pressure and its variation inside RPC200 at various temperatures.A thin-wall spherical pore model was proposed to analyze the thermo-mechanical mechanism of spalling,by which the stresses varying with the vapor pressure q(T) and the characteristic size of wall(K) at any point of interest were determined.It is shown that the pore characteristics including specific pore volume,average pore size,threshold pore size and most probable pore size rise significantly with the increasing temperature.200℃ appears to be the threshold temperature above which the threshold pore size and the most probable pore size climb up dramatically.The increase in the specific pore volume results from the growth both in quantity and in volume of the transition pores and the capillary pores.The appearance of the explosive spalling in RPC200 is mainly attributed to being unable to form pathways in favor of releasing water steam in RPC and to the rapid accumulation of high vapor pressures as well.The thin-wall sphere domain where the vapor pressure governs the spalling is bounded through the pore model. | JU Yang LIU HongBin TIAN KaiPei LIU JinHui WANG Li GE ZhiShun | 2013 | Science China(Technological Sciences)2013，56，2： | 8 |
| 10 | Comparison of activated carbon and iron/cerium modified activated carbon to remove methylene blue from wastewater显示文摘The methylene blue(MB)removal abilities of raw activated carbon and iron/cerium modified raw activated carbon(Fe–Ce-AC)by adsorption were researched and compared.The characteristics of Fe–Ce-AC were examined by N_2adsorption,zeta potential measurement,FTIR,Raman,XRD,XPS,SEM and EDS.After modification,the following phenomena occurred:The BET surface area,average pore diameter and total pore volume decreased;the degree of graphitization also decreased.Moreover,the presence of Fe_3O_4led to Fe–Ce-AC having magnetic properties,which makes it easy to separate from dye wastewater in an external magnetic field and subsequently recycle.In addition,the equilibrium isotherms and kinetics of MB adsorption on raw activated carbon and Fe–Ce-AC were systematically examined.The equilibrium adsorption data indicated that the adsorption behavior followed the Langmuir isotherm,and the pseudo-second-order model matched the kinetic data well.Compared with raw activated carbon,the maximum monolayer adsorption capacity of Fe–Ce-AC increased by27.31%.According to the experimental results,Fe–Ce-AC can be used as an effective adsorbent for the removal of MB from dye wastewater. | Song Cheng Libo Zhang Aiyuan Ma Hongying Xia Jinhui Peng Chunyang Li Jianhua Shu | 2018 | Journal of Environmental Sciences2018，30，3： | 8 |
| 11 | Activity and hydrothermal stability of CeO_2–ZrO_2–WO_3 for the selective catalytic reduction of NO_x with NH_3显示文摘A series of CeO_2–ZrO_2–WO_3(CZW)catalysts prepared by a hydrothermal synthesis method showed excellent catalytic activity for selective catalytic reduction(SCR)of NO with NH_3 over a wide temperature of 150–550°C.The effect of hydrothermal treatment of CZW catalysts on SCR activity was investigated in the presence of 10% H_2O.The fresh catalyst showed above 90% NO_x conversion at 201–459°C,which is applicable to diesel exhaust NO_x purification(200–440°C).The SCR activity results indicated that hydrothermal aging decreased the SCR activity of CZW at low temperatures(below 300°C),while the activity was notably enhanced at high temperature(above 450°C).The aged CZW catalyst(hydrothermal aging at 700°C for 8 hr)showed almost 80% NO_x conversion at 229–550°C,while the V_2O_5–WO_3/TiO_2 catalyst presented above 80% NO_x conversion at 308–370°C.The effect of structural changes,acidity,and redox properties of CZW on the SCR activity was investigated.The results indicated that the excellent hydrothermal stability of CZW was mainly due to the CeO_2–ZrO_2 solid solution,amorphous WO_3 phase and optimal acidity.In addition,the formation of WO_3 clusters increased in size as the hydrothermal aging temperature increased,resulting in the collapse of structure,which could further affect the acidity and redox properties. | Zhongxian Song Ping Ning Qiulin Zhang Hao Li Jinhui Zhang Yancai Wang Xin Liu Zhenzhen Huang | 2016 | Journal of Environmental Sciences2016，28，4： | 7 |
| 12 | Gold mineralization age of the Anjiayingzi gold deposit in Chifeng County, Inner Mongolia and implications for Mesozoic metallogenic explosion in North China显示文摘The Anjiayingzi gold deposit in Chifeng County, Inner Mongolia is located in the central part of the gold mineralization belt of the northern margin of the North China Craton (NCC), and is adjacent to the Paleozoic Inner Mongolia-Da Hinggan Mountains orogenic belt in the north. The Chifeng-Kaiyuan fault, which separates the NCC from this orogenic belt, is considered to be a regional ore-controlling structure. The Anjiayingzi gold deposit is a mediate-size quartz lode-gold deposit and is hosted by the Anjiayingzi quartz monzonite that was emplaced into the basement composed of early Precambrian gneisses. Rhyolitic and porphyritic dikes are generally associated with the gold mineralization. Zircon U-Pb analyses suggest that the Anjia- yingzi granite was emplaced from 132 Ma to 138 Ma, while the rhyolitic dikes that occupy the same fracture system as the gold-bearing quartz veins and locally crosscut the gold lodes crystallized from 125 Ma to 127 Ma. These results constrain the mineralization age between 126 Ma and 132 Ma, early Cretaceous time for the Anjiayingzi gold deposit. This mineralization age is consistent with that of the gold deposits in other major gold-bearing areas of the NCC, such as the Jiaodong Peninsula and the Xiaoqinling Mountain, and specially is roughly coeval with the geodynamic reversion of the NCC in Mesozoic. This coincidence probably indicates that the gold deposits in the NCC, including the Anjiayingzi deposit, formed in a similar geodynamic setting characterized by large-scale thinning of the lithosphere underlying the NCC. | LI Yonggang ZHAI Mingguo YANG Jinhui MIAO Laicheng GUAN Hong | 2004 | Science China Earth Sciences2004，47，2： | 7 |
| 13 | Synthesis and electrochemical performances of LiCoO_2 recycled from the incisors bound of Li-ion batteries显示文摘A new LiCoO2 recovery technology for Li-ion batteries was studied in this paper. LiCoO2 was peeled from the Al foil with dimethyl acetamide (DMAC), and then polyvinylidene fluoride (PVDF) and carbon powders in the active material were eliminated by high temperature calcining. Subsequently, Li2CO3, LiOH·H2O and LiAc·2H2O were added into the recycled powders to adjust the Li/Co molar ratio to 1.00. The new LiCoO2 was obtained by calcining the mixture at 850°C for 12 h in air. The structure and morphology of the recycled powders and resulting samples were studied by XRD and SEM techniques, respectively. The layered structure of LiCoO2 synthesized by adding Li2CO3 is the best, and it is found to have the best characteristics as a cathode material in terms of charge-discharge capacity and cycling performance. The first discharge capacity is 160 mAh·g-1 between 3.0-4.3 V. The discharge capacity after cycling for 50 times is still 145.2 mAh·g-1. | LI Jinhui ZHONG Shengwen XIONG Daoling CHEN Hao | 2009 | Rare Metals2009，28，4： | 6 |
| 14 | Oxygen and nitrogen-doped metal-free carbon catalysts for hydrochlorination of acetylene显示文摘Activated carbon was tested as metal-free catalyst for hydrochlorination of acetylene in order to circumvent the problem of environment pollution caused by mercury and high cost by noble metals. Oxygen-doped and nitrogen-doped activated carbons were prepared and characterized by XPS, TPD and N2 physisorption methods.The influences of the surface functional groups on the catalytic performance were discussed base on these results.Among all the samples tested, a nitrogen-doped sample, AC-n-U500, exhibited the best performance, the acetylene conversion being 92% and vinyl chloride selectivity above 99% at 240 °C and C2H2 hourly space velocity30 h-1. Moreover, the AC-n-U500 catalyst exhibited a stable performance during a 200 h test with a conversion of acetylene higher than 76% at 210 °C at a C2H2 hourly space velocity 50 h-1. In contrary, oxygen-doped catalyst had lower catalytic activities. A linear relationship between the amount of pyrrolic-N and quaternary-N species and the catalytic activity was observed, indicating that these nitrogen-doped species might be the active sites and the key in tuning the catalytic performance. It is also found that the introduction of nitrogen species into the sample could significantly increase the adsorption amount of acetylene. The deactivation of nitrogendoped activated carbon might be caused by the decrease of the accessibility to or the total amount of active sites. | Tongtong Zhang Jia Zhao Jiangtao Xu Jinhui Xu Xiaoxia Di Xiaonian Li | 2016 | Chinese Journal of Chemical Engineering2016，24，4： | 6 |
| 15 | Development and utilization of a new chemically-induced soybean library with a high mutation density显示文摘Mutagenized populations have provided important materials for introducing variation and identifying gene function in plants. In this study, an ethyl methanesulfonate(EMS)-induced soybean(Glycine max) population,consisting of 21,600 independent M_2 lines, was developed.Over 1,000 M_(4(5))families, with diverse abnormal phenotypes for seed composition, seed shape, plant morphology and maturity that are stably expressed across different environments and generations were identified. Phenotypic analysis of the population led to the identification of a yellow pigmentation mutant, gyl, that displayed significantly decreased chlorophyll(Chl) content and abnormal chloroplast development. Sequence analysis showed that gyl is allelic to Minn Gold, where a different single nucleotide polymorphism variation in the Mg-chelatase subunit gene(ChlI1a) results in golden yellow leaves. A cleaved amplified polymorphic sequence marker was developed and may be applied to marker-assisted selection for the golden yellow phenotype in soybean breeding. We show that the newly developed soybean EMS mutant population has potential for functional genomics research and genetic improvement in soybean. | Zhongfeng Li Lingxue Jiang Yansong Ma Zhongyan Wei Huilong Hong Zhangxiong Liu Jinhui Lei Ying Liu Rongxia Guan Yong Guo Longguo Jin Lijuan Zhang Yinghui Li Yulong Ren Wei He Ming Liu Nang Myint Phyu Sin Htwe Lin Liu Bingfu Guo Jian Song Bing Tan Guifeng Liu Maiquan Li Xianli Zhang Bo Liu Xuehui Shi Sining Han Sunan Hua Fulai Zhou Lili Yu Yanfei Li Shuang Wang Jun Wang Ruzhen Chang Lijuan Qiu | 2017 | Journal of Integrative Plant Biology2017，59，1： | 6 |
| 16 | In situ calcite U-Pb geochronology by high-sensitivity single-collector LA-SF-ICP-MS显示文摘U-Pb geochronology of calcite using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) is an emerging method,with potential applications to a vast array of geological problems.Due to the low levels of U and Pb in calcite,measurement using higher-sensitivity instruments,such as sector field (SF) ICP-MS,have advantages over more commonly used quadrupole (Q) ICP-MS instruments.Using a Thermo Element XR ICP-MS,we demonstrate that the Jet+X cone combination with the N_(2) enhancement technique provides the best sensitivity for measuring U and Pb isotopes.This higher sensitivity improves the precision of calcite U-Pb isotope measurements,and permits dating at high spatial resolutions (<110μm) and for samples containing low contents of^(238)U (<1μg g^(–1)) and/or^(207)Pb (i.e.,young samples<10 Ma).Using a spot size of 85μm with a low fluence (~2.0 J cm^(–2)),the laser-induced elemental fractionation of^(206)Pb/^(238)U in the NIST SRM 614,ARM-3 and WC-1 reference materials are insignificant (<2.2%).Adopting the optimized instrument parameters,we analysed four commonly-used calcite U-Pb reference materials (WC-1,Duff Brown Tank,JT,and ASH-15).The results match well with published isotope dilution data,demonstrating the reliability of our technique.ARM-3,an andesitic glass,is shown to be an appropriate reference material for both^(207)Pb/^(206)Pb calibration and instrument optimization because of its moderate contents of U(~3.75μg g^(–1)) and Pb (~12.7μg g^(–1)).We further demonstrate that the image-guided approach using LA-ICP-MS elemental mapping is an efficient tool in obtaining robust ages. | Shitou WU Yueheng YANG Nick M.W.ROBERTS Ming YANG Hao WANG Zhongwu LAN Bohang XIE Tianyi LI Lei XU Chao HUANG Liewen XIE Jinhui YANG Fuyuan WU | 2022 | Science China Earth Sciences2022，65，6： | 6 |
| 17 | First Total Synthesis of (±)-Puyanin and (±)-4'-O-Methylbonannione显示文摘为二自然地发生的 geranylated flavonoids 的第一全部的合成的一条灵巧的途径,( | Zhang, Yuheng Yang, Jinhui Li, Hongjun Jiang, Shizhi Li, Yunfeng Liu, Wanyi | 2011 | Chinese Journal of Chemistry2011，29，3： | 6 |
| 18 | Biocatalytic desymmetrization of 3-substituted glutaronitriles by nitrilases. A convenient chemoenzymatic access to optically active (S)-Pregabalin and (R)-Baclofen显示文摘Desymmetrization of prochiral 3-substituted glutaronitriles offers a new approach to access(S)-Pregabalin and(R)-Baclofen. A number of nitrilases from diverse sources were screened with 3-isobutylglutaronitriles(1a) or 3-(4′-chlorophenyl)glutaronitriles(1b) as the substrate. Some nitrilases were found to catalyze the desymmetric hydrolysis of 1a and 1b to form optically active 3-(cyanomethyl)-5-methylhexanoic acid(2a) and 3-(4′-chlorophenyl)-4-cyanobutanoic acid(2b) with high enantiomeric excesse(ee), respectively. This cannot be achieved using traditional chemical hydrolysis. Among them, AtNIT3 generated(R)-2b, whereas BjNIT6402 and HsNIT produced the opposite(S)-enantiomer with high conversions and ee values. Not only the nitrilases showed different activities and stereoselectivities toward these 3-substituted glutaronitriles, the 3-substituent of the substrates also exerted great effect on the enzyme activity and stereoselectivity.(S)-2a and(S)-2b were prepared with high yields and ee values using BjNIT6402 and HsNIT as the biocatalysts, respectively. A straightforward Curtius rearrangement of(S)-2a and(S)-2b, followed by the acidic hydrolysis, afforded(S)-Pregabalin and(R)-Baclofen. This offers a new platform methodology for the synthesis of optically active β-substituted γ-amino acids of pharmaceutical importance. | DUAN YiTao YAO PeiYuan REN Jie HAN Chao LI Qian YUAN Jing FENG JinHui WU QiaQing ZHU DunMing | 2014 | Science China Chemistry2014，57，8： | 6 |
| 19 | Sub-10-fs pulse generation directly from a KLM Ti: sapphire laser显示文摘By reducing the effects of frequency dependent mode size and intracavity gain saturation of a KLM Ti: sapphire laser, the pulse bandwidth broadening is enhanced significantly. 8.5 fs pulses with the bandwidth of 92 nm at wavelength of 710 nm have been generated directly from this laser and measured with an extracavity group velocity dispersion compensation system. | Weizhu Lin Rui Liao Jinhui Wen Zhigang Liu Li Deng Haichao Zhang Tianshu Lai | 2002 | Chinese Science Bulletin2002，47，12： | 5 |
| 20 | Overview and outlook on railway track stiffness measurement显示文摘Stiffness is one of the basic performance parameters for railway track. The efficient and accurate stiffness measurement has been considered as the foundation for further development of railway engineering, and therefore has great theoretical and practical significance.Based on a summary of the connotation and measurement of track stiffness, the state of the art of measurement methods for track stiffness was analyzed systematically.The standstill measurement of track stiffness can be performed with the traditional jack-loading method, impact hammer method, FWD(falling weight deflectometer)method, and track loading vehicle method. Although these methods can be adopted in stiffness measurement for a section of railway track, they are not desirable owning to small range and low efficiency. In the recent 20 years,researchers have proposed many methods like unbalancedloading laser displacement method, deflection basin deformation rate method, and eccentricity excitation method to continuously measure track stiffness; however,these methods have drawbacks like poor accuracy, low speed, and insufficient data analysis. In this work, the merits and demerits of these methods were summarized,and optimization suggestions were presented. Based on the wave transmission mechanism and principle of vibration energy harvesting, an overall conception on continuous measurement of stiffness and long-term stiffness monitoring for special sections was proposed. | Ping Wang Li Wang Rong Chen Jinhui Xu Jinmang Xu Mingyuan Gao | 2016 | Journal of Modern Transportation2016，24，2： | 5 |
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