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Seven New Sesquiterpene Lactones from Eupatorium chinense

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Chinese Journal of Chemistry 2005年第11期23卷 1530-1536页

作者： yang, Sheng-Ping CHENG, Jia-Gao HUO, Jun jianG, Hua-Liang CHEN, kai-Xian YUE, jian-Min State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Zhangjiang Hi-Tech Park Shanghai 201203 China

Seven new sesquiterpenoids, namely eupatochinilides Ⅰ-Ⅶ （1-7）, together with eight known compounds, euponin （8）, mollisorin A （9）, niveusin B （10）, 8β-（4＇-acetoxy-tiglyloxy）-3β-hydroxy-6Hβ,7Hα-germacra-1（10）E,4E,11（13）-trien-6,12-olide （11）, eupalinifide B （12）, 8β-（4＇-hydroxytigloyloxy）-5-desoxy-8-desacyleuparotin （13）, 3-deacetyeupalinin A （14）, and 15-hydroxyleptocarpin （15）, were isolated from the ethanolic extract of the whole plant of Eupatorium chinense L. Their structures and stereochemistry were established by spectroscopic methods and GIAO based ^13C NMR chemical shift calculations.

关键词： Eupatorium chinense sesquiterpenoid eupatochinilides Ⅰ-Ⅶ gauge-independent atomic orbital,quantum chemical calculation

Effect of ultraviolet mutagenesis on heterotrophic strain mutation and bioleaching of low grade copper ore

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Journal of Central South University 2017年第10期24卷 2245-2252页

作者： WU Ai-xiang HU kai-jian WANG Hong-jiang ZHANG Ai-qing yang Ying School of Civil and Environmental Engineering University of Science and Technology Beijing School of Resources and Environmental Engineering Jiangxi University of Science and Technology

The effect of ultraviolet mutagenesis on a heterotrophic strain(Providencia JAT-1) mutation was studied and bioleaching of low grade copper ore with mutant bacteria was investigated. The results show that the activity of bacteria was improved after ultraviolet mutagenesis; the best irradiation time was 120 s. Compared to the original bacteria, the cells density of mutant bacteria at stationary phase increased by 26% and ammonia produced by mutant bacteria increased by 12%. Higher activity of bacteria leads to a higher copper extraction rate. The bioleaching performance of Providencia JAT-1 was improved after UV mutagenesis. The copper extraction rate with mutant bacteria increased by 10.6% compared to the original bacteria. The ore surface was corroded and the fine particles were absent after bioleaching. Free copper oxide and copper silicates could be leached out easily by using JAT-1; a small part of the copper sulfide can also be leached out. Bioleaching using JAT-1 is more effective than ammonia leaching and copper extraction rate with mutant bacteria was 21.1% higher than that by ammonia leaching under the same condition.

关键词： ultraviolet mutagenesis bioleaching heterotrophic strain ammonia low grade copper ore

Studied microRNA gene expression in human hepatocellular carcinoma by micro RNA microarray techniques

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World Journal of Gastroenterology 2015年第44期21卷 12605-12611页

作者： jian-Xiang Niu Xing-kai Meng jian-Jun Ren Department of General Surgery of the Affiliated Hospital of Inner Mongolia Medical University

AIM: To achieve a better understanding of the molecular mechanisms of micro RNA expression changes involved in hepatocellular ***: In this research process, patients were not treated with antivirals, immunosuppressants or immunomodulators for at least 6 mo before collecting serum. The study population was composed of 35 outpatient hepatitis B virus(HBV) cases and 12 healthy control cases from the Affiliated Hospital of Inner Mongolia Medical University(Inner Mongolia, China) from July 2013 to April 2014. The 35 HBV cases were divided into two groups: a hepatocirrhosis group with 20 cases and a liver cancer group with 15 cases. All 35 cases carried HBs Ag. The diagnostic criteria followed the European Association for the Study of the Liver 2012(EASL2012) standards. Micro RNA(mi RNA) was extracted from a control group of patients, a group with hepatocirrhosis and a group with liver cancer and its quality was analyzed using the human V2 micro RNA expression beadchip. Cluster analysis and a radar chart were then applied to the mi RNA ***: The mi RNA-qualified rate of human serum samples was 93%. The concentration of a single sample was > 200 ng/μL and the volume was > 5 μ*** mi RNA serum samples were uncontaminated by the genome. The Mann-Whitney test showed significant differences in mi RNA between each group, with a detection P-value of < 0.05. Illumina software was set up with Diff Score set to ± 13, meaning that P = *** were significant changes in mi RNA expression between the three groups. mi RNA-183 was the most up-regulated, followed by mi RNA-373. mi RNA-129 and mi RNA-188 were both strongly down-regulated and mi RNA-378 was down-regulated a small amount. The liver cancer group had greater changes, which indicated that changes in mi RNA expression levels were caused by hepatocirrhosis. The liver cancer disease course then further increased these changes. In the pentagon created by these five mi RNAs, three groups showed signif

关键词： Hepatocellular carcinoma Micro RNA Expression Micr

Multi-surrogate framework with an adaptive selection mechanism for production optimization

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Petroleum Science 2024年第1期21卷 366-383页

作者： Jia-Lin Wang Li-Ming Zhang kai Zhang jian Wang jian-Ping Zhou Wen-Feng Peng Fa-Liang Yin Chao Zhong Xia Yan Pi-yang Liu Hua-Qing Zhang Yong-Fei yang Hai Sun School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Qingdao University of Technology Qingdao266580ShandongChina College of Science China University of PetroleumQingdao266580ShandongChina Zepu Oil and Gas Development Department PetroChina Tarim Oilfield CompanyKorla841000XinjiangChina Hainan Branch of CNOOC Ltd Haikou70311HainanChina

Data-driven surrogate models that assist with efficient evolutionary algorithms to find the optimal development scheme have been widely used to solve reservoir production optimization ***,existing research suggests that the effectiveness of a surrogate model can vary depending on the complexity of the design problem.A surrogate model that has demonstrated success in one scenario may not perform as well in *** the absence of prior knowledge,finding a promising surrogate model that performs well for an unknown reservoir is ***,the optimization process often relies on a single evolutionary algorithm,which can yield varying results across different *** address these limitations,this paper introduces a novel approach called the multi-surrogate framework with an adaptive selection mechanism(MSFASM)to tackle production optimization *** consists of two *** the first stage,a reduced-dimensional broad learning system(BLS)is used to adaptively select the evolutionary algorithm with the best performance during the current optimization *** the second stage,the multi-objective algorithm,non-dominated sorting genetic algorithm II(NSGA-II),is used as an optimizer to find a set of Pareto solutions with good performance on multiple surrogate models.A novel optimal point criterion is utilized in this stage to select the Pareto solutions,thereby obtaining the desired development schemes without increasing the computational load of the numerical *** two stages are combined using sequential transfer *** the two most important perspectives of an evolutionary algorithm and a surrogate model,the proposed method improves adaptability to optimization problems of various reservoir *** verify the effectiveness of the proposed method,four 100-dimensional benchmark functions and two reservoir models are tested,and the results are compared with those obtained by six other surrogate-model-based *** res

关键词： Production optimization Multi-surrogate models Multi-evolutionary algorithms Dimension reduction Broad learning system

Microreaction Technology for Synthetic Chemistry

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Chinese Journal of Chemistry 2019年第2期37卷 161-170页

作者： jian Deng Jisong Zhang kai Wang Guangsheng Luo The State Key Lab of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Microreaction technology as an emerging tool for synthetic chemistry has been extensively applied in academic and industrial researches. Normally, synthetic chemists used to running reactions in the classical glassware for cen turies are unfamiliar and unaccustomed to use microreaction tech no logy for routine synthetic work. This review tries to give a general introduction of the capabilities of microreaction tech no logy.

关键词： Microreaction Technology Synthetic Chemistry

A 128×128 SPAD LiDAR sensor with column-parallel 25 ps resolution TA-ADCs

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Journal of Semiconductors 2024年第8期45卷 34-40页

作者： Na Tian Zhe Wang kai Ma Xu yang Nan Qi jian Liu Nanjian Wu Runjiang Dou Liyuan Liu State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

This paper presents a design of single photon avalanche diode(SPAD)light detection and ranging(LiDAR)sensor with 128×128 pixels and 128 column-parallel time-to-analog-merged-analog-to-digital converts(TA-ADCs).Unlike the conventional TAC-based SPAD LiDAR sensor,in which the TAC and ADC are separately implemented,we propose to merge the TAC and ADC by sharing their capacitors,thus avoiding the analog readout noise of TAC’s output buffer,improving the conversion rate,and reducing chip *** reverse start-stop logic is employed to reduce the power of the *** in a 180 nm CMOS process,our prototype sensor exhibits a timing resolution of 25 ps,a DNL of+0.30/−0.77 LSB,an INL of+1.41/−2.20 LSB,and a total power consumption of 190 mW.A flash LiDAR system based on this sensor demonstrates the function of 2D/3D imaging with 128×128 resolution,25 kHz inter-frame rate,and sub-centimeter ranging precision.

关键词： 3D imaging CMOS imagers direct time-of-flight(dTOF) time-to-analog converter(TAC)

An Interconnected Multi-Plane Multi-Stage Fault-Tolerant On-Board Switching Fabric

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China Communications 2015年第2期12卷 74-83页

作者： LIU kai YAN jian CHEN Xiang LU jianhua Department of Electronic Engineering/Graduate School at Shenzhen Tsinghua University Tsinghua Space Center Tsinghua University Department of Electronic Engineering Tsinghua University

The harsh space radiation environment compromises the reliability of an on-board switching fabric by leading to cross-point and switching element(SE)*** from traditional faulttolerant switching fabrics only taking crosspoint faults into account,a novel Input and Output Parallel Clos network,referred to as the(p_1,p_2)-IOPClos,is proposed to tolerate both cross-point and SE *** the(p_1,p_2)-IOPClos,there are p_1 and p_2 expanded parallel switching planes in the input and output stages,*** multiple input/output switching planes are interconnected through the middle stage to provide multiple paths in each stage by which the network throughput can be increased ***,the network reliability of the(p_1,p_2)-IOPClos under the above both kinds of faults is *** corresponding implementation cost is also presented along with the network *** theoretical analysis and numerical results indicate that the(p_1,p_2)-IOPClos outperforms traditional Clos-type networks at reliability,while has less implementation cost than the multi-plane Clos network.

关键词： on-board switching fabric clos network reliability

Regulation of mixed Ag valence state by non-thermal plasma for complete oxidation of formaldehyde

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Chinese Chemical Letters 2022年第1期33卷 434-437页

作者： kai Li jian Ji Yanling Gan Haibao Huang School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou 510006China Guangdong Indoor Air Pollution Control Engineering Research Center Guangzhou 510006China

Formaldehyde is an important air pollutant and its removal is essential to protect human health and meet environmental ***-based catalyst has a considerable potential for HCHO oxidation in low temperature *** valence state of Ag is one of the key roles in formaldehyde catalytic ***,its effect on activity is still ***-thermal plasma and conventional calcination were employed to regulate Ag valence state in this *** Ag-Co/CeO_(2)catalysts with totally different distribution of Ag species were obtained.A special mixed Ag valence state,~50%Ag^(δ+)with a few Ag^(0)and Ag^(+),was achieved by plasma *** had the merits of both good activity and stability.A close relationship between Ag valence state and the activity for HCHO oxidation was *** activity of different Ag species follows the order:Ag^(δ+)+Ag^(0)+Ag^(+)>Ag^(δ+)>Ag^(0)>Ag^(+).

关键词： Ag valence Non-thermal plasma HCHO Complete oxidation Ag-based catalyst

Characteristics of Caragana korshinskii and Hippophae rhamnoides stemflow and their significance in soil moisture enhancement in Loess Plateau, China

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Journal of Arid Land 2014年第1期6卷 105-116页

作者： ShengQi jian ChuanYan ZHAO ShuMin FANG kai YU State Key Laboratory of Grassland and Agro-Ecosystems School of Life SciencesLanzhou University College of Resource and Environmental Sciences Gansu Agricultural University Ministry of Education Key Laboratory of Western China Environmental Systems Lanzhou University

Stemflow of xerophytic shrubs represents a significant component of water replenishment to the soil-root system and influences water utilization of plant roots at the stand scale,especially in water-scarce semi-arid *** stemflow of two semi-arid shrubs(Caragana korshinskii and Hippophae rhamnoides)and its effect on soil moisture enhancement were evaluated during the growing season of 2011 in the semi-arid loess region of *** results indicated that stemflow averaged 12.3%and 8.4%of the bulk precipitation for *** and ***,*** stemflow increased in a linear function with increasing rainfall *** relationship between funneling ratios and rainfall suggested that there existed a rainfall depth threshold of 11 mm for both *** and *** funneling ratios were 156.6±57.1 and49.5±30.8 for *** and ***,respectively,indicating that the canopy architecture of the two shrubs was an effective funnel to channel stemflow to the root area,and *** showed a greater potential to use stemflow water in the semi-arid *** individual rainfall events,the wetting front depths were approximately 2 times deeper in the rooting zone around the stems than in the bare area outside canopy for both *** and ***,soil water content was also significantly higher in the root area around the shrub stem than in the area outside the shrub *** confirms that shrub stemflow conserved in the deep soil layers may be an available moisture source for plant growth under semi-arid conditions.

关键词： precipitation stemflow funneling ratio rainfall intensity Anjiapo catchment