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Chinese Journal of Chemistry 2021年第7期39卷 1916-1922页

作者： xian-liang wang Xing-Hao Yin Jun-Zhao Xiao Xue-Shun Jia liang Yin CAS Key Laboratory of Synthetic Chemistry of Natural Substances Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai200032 China Department of Chemistry Shanghai University99 Shangda RoadShanghai200444 China

Main observation and conclusion A general synthesis of chiral 1,3-disubstituted allylsilanes is established through copper(I)-catalyzed asymmetric 1,4-conjugate silylation ofα,β-unsaturated sulfones and subsequent Julia-Kocienski *** modification of McQuade's NHC ligand,the catalytic asymmetric conjugate silylation with a broad substrate scope is achieved in high enantioselectivity.

关键词： Chiral allylsilanes Silylation Olefination Allylation Asymmetric catalysis

Prediction of oxygen concentration and temperature distribution in loose coal based on BP neural network

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Mining Science and Technology 2009年第2期19卷 216-219页

作者： ZHANG Yong-jian WU Guo-guang XU Hong-feng MENG xian-liang wang Guang-you School of Chemical Engineering and Technology China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

An effective method for preventing spontaneous combustion of coal stockpiles on the ground is to control the air-flow in loose coal. In order to determine and predict accurately oxygen concentrations and temperatures within coal stockpiles, it is vital to obtain information of self-heating conditions and tendencies of spontaneous coal combustion. For laboratory conditions, we designed our own experimental equipment composed of a control-heating system, a coal column and an oxygen concentration and temperature monitoring system, for simulation of spontaneous combustion of block coal （13-25 mm） covered with fine coal （0-3 mm）. A BP artificial neural network （ANN） with 150 training samples was gradually established over the course of our experiment. Heating time, relative position of measuring points, the ratio of fine coal thickness, artificial density, voidage and activation energy were selected as input variables and oxygen concentration and temperature of coal column as output variables. Then our trained network was applied to predict the trend on the untried experimental data. The results show that the oxygen concentration in the coal column could be reduced below the minimum still able to induce spontaneous combustion of coal - 6% by covering the coal pile with fine coal, which would meet the requirement to prevent spontaneous combustion of coal stockpiles. Based on the prediction of this ANN, the average errors of oxygen concentration and temperature were respectively 0.5% and 7 ℃, which meet actual tolerances. The implementation of the method would provide a practical guide in understanding the course of self-heating and spontaneous combustion of coal stockpiles.

关键词： loose coal neural netwOrk spontaneous combustion of coal oxygen concentration temperature prediction

Electrically tunable phase-change metasurface for dynamic infrared thermal camouflage

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Photonics Research 2024年第2期12卷 292-300页

作者： YUFENG XIONG YUNZHENG wang CHAO FENG YAOLAN TIAN liang GAO JUN-LEI wang ZHUANG ZHUO xian ZHAO Center for Optics Research and Engineering Key Laboratory of Laser&Infrared SystemMinistry of EducationShandong UniversityQingdao 266237China School of Information Science and Engineering Shandong UniversityQingdao 266237China

Dynamic infrared thermal camouflage technology has attracted extensive attention due to its ability to thermally conceal targets in various environmental backgrounds by tuning thermal *** use of phase change materials(PCMs)offers numerous advantages,including zero static power,rapid modulation rate,and large emissivity tuning ***,existing PCM solutions still encounter several practical application challenges,such as temperature uniformity,amorphization achievement,and adaptability to different *** this paper,we present the design of an electrically controlled metal-insulator-metal thermal emitter based on a PCM metasurface,and numerically investigate its emissivity tunability,physical mechanisms,heat conduction,and thermal camouflage performance across different ***,the influence of the quench rate on amorphization was studied to provide a guidance for evaluating and optimizing device *** results reveal that the thermal emitter exhibits a wide spectral emissivity tuning range between 8 and 14μm,considerable quench rates for achieving amorphization,and the ability to provide thermal camouflage across a wide background temperature ***,it is anticipated that this contribution will promote the development of PCM-based thermal emitters for practical dynamic infrared thermal camouflage technology with broad applications in both civilian and military domains.

关键词： thermal dynamic phase

Method for rapid warning and activity concentration estimates in online waterγ-spectrometry systems

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Nuclear Science and Techniques 2024年第3期35卷 1-12页

作者： Meng wang Yi Gu Mao-Lin Xiong liang-Quan Ge Qing-xian Zhang Guo-Qiang Zeng Heng Lu Sheng-liang Guo College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province (Chengdu University of Technology)Chengdu 610059China Chengdu New Ray Technology Co.Ltd Chengdu 610052China

Onlineγ-spectrometry systems for inland waters,most of which extract samples in situ and in real time,are able to produce reliable activity concentration measurements for waterborne radionuclides only when they are distributed relatively uniformly and enter into a steady-state diffusion regime in the measurement *** protect residents’health and ensure the safety of the living environment,better timeliness is required for this measurement *** address this issue,this study established a mathematical model of the online waterγ-spectrometry system so that rapid warning and activity estimates can be obtained for water under non-steady-state(NSS)*** addition,the detection efficiency of the detector for radionuclides during the NSS diffusion process was determined by applying the computational fluid dynamics technique in conjunction with Monte Carlo *** this basis,a method was developed that allowed the online waterγ-spectrometry system to provide rapid warning and activity concentration estimates for radionuclides in *** analysis of the NSS-mode measurements of^(40)K radioactive solutions with different activity concentrations determined the optimum warning threshold and measurement time for producing accurate activity concentration estimates for *** experimental results show that the proposed NSS measurement method is able to give warning and yield accurate activity concentration estimates for radionuclides 55.42 and 69.42 min after the entry of a 10 Bq/L^(40)K radioactive solution into the measurement chamber,*** times are much shorter than the 90 min required by the conventional measurement ***,the NSS measurement method allows the measurement system to give rapid(within approximately 15 min)warning when the activity concentrations of some radionuclides reach their respective limits stipulated in the Guidelines for Drinking-water Quality of the WHO,suggesting that this method con

关键词： Water radioactivity monitoring Dynamic detection efficiency Rapid warning Activity estimation

Remolding Diversified Objects in Ada95: Toward A Object Pattern

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Wuhan University Journal of Natural Sciences 2001年第Z1期6卷 247-255页

作者： liang xian zhong, wang Zhen yu Wuhan Digital Engineering Institute P. O. Box 74223, Wuhan 430074, China Wuhan Digital Engineering Institute Wuhan China

Ada provides full capacities of supporting object orientation, but the diversified objects patterned in Ada are so intricate that Ada95's aim would be demolished. In order to complement the disfigurement that Ada does lack for a pristine notion of class, this paper presents a remolded object pattern known as A object, an Ada based class description language A ObjAda aiming at support for A object pattern and the related approach for key algorithms and implementation. In consequent, A ObjAda hereby promotes Ada with highlighted object orientation, which not only effectively exploits the capacities in Ada95, but also rationally hides befuddling concepts from Ada95.

关键词： ADT (abstract data type) ASM (abstract state machine) V object U object A object pattern

Event-based Implicit Invocation Decentralized in Ada

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Wuhan University Journal of Natural Sciences 2001年第Z1期6卷 239-246页

作者： liang xian zhong, wang Zhen yu Wuhan Digital Engineering Institute, P. O. Box 74223, Wuhan 430074, China Wuhan Digital Engineering Institute Wuhan China

Nowadays more and more attraction is drawn by the event based implicit invocation one of useful architectural patterns, because of its loose coupling between components in the architecture and reactive integration in software systems. Analyzing object oriented interaction with objects, this paper, based upon the principle of software architecture, presents an approach on event based object model with Ada exception handler. Consequently it is possible for us to improve, with adding specific architectural patterns, traditional programming languages into architectural description languages.

关键词： implicit invocation architectural pattern EBO (event based object) exception handler

Double-endpoint Genotoxicity Quantification and PAHs Characterization of Drinking Water Source alongside Polluted Yinghe River with High Tumor Mortality

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Current Medical Science 2021年第2期41卷 189-198页

作者： Wei ZHANG Chen GUO Xiao-li wang Zhan-lu LV Lin FAN Yu-yan YANG Xu LI Jing QI Shu-li ZHAO xian-liang wang China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijing 100021China China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China College of Life Science and Bioengineering Beijing University of TechnologyBeijing 100124China China National Environmental Monitoring Center Beijing 100012China

The etiology for the high tumor mortality in heavy polluted Yinghe river basin is still unclear and polycyclic aromatic hydrocarbons(PAHs)belong to the priority pollutants in water based on the former surveillance *** order to explore the potential genotoxicants contributing to the double-endpoint genotoxicity of polluted drinking water source,12 groundwater and 3 surface water samples were collected from 3 villages and the nearby rivers alongside Yinghe river basin,respectively and their comprehensive genotoxicity was estimated with a bioassay group of sOS/umu test and micronucleus(MN)test(MNT).Some groundwater samples showed positive genotoxicity and all surface water samples were highly *** groundwater samples showed DNA genotoxic effct with the average 4-NQO equivalent concentration(TEQ_(4-NQO))of 0.067μg/L and 0.089μg/L in wet and dry season,*** average MN ratios of groundwater samples were 14.19‰ and 17.52‰ in wet and dry season,*** samples showed different genotoxic effect among 3 *** total PAHs concentrations in all water samples ranged from 8.98 to 25.17 ng/L with an average of 14.97±4.85 ng/***,CHR,BkF,BaP and DBA were the main carcinogenic PAHs contributing to the genotoxicity of water *** conclusion,carcinogenic PAHs are possibly related to the high tumor mortality in the target *** of carcinogenic PAHs to genotoxicity of drinking water source may shed light on the etiology study for high tumor mortality in Yinghe river *** words:genotoxicity test;drinking water source;high tumor mortality;Yinghe river basin;polycyclic aromatic hydrocarbons(PAHs)

关键词： genotoxicity test drinking water source high tumor mortality Yinghe river basin polycyclic aromatic hydrocarbons(PAHs)

Intelligent reflecting surfaces-assisted millimeter wave communication:Channel estimation based on deep learning

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The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 49-56页

作者： Kang Xiaofei wang Tian liang xian College of Communication and Information Engineering Xi'an University of Science and TechnologyXi'an 710600China

In response to the challenge posed by the complexity of the system and the difficulty in obtaining accurate channel state information(CSI)for millimeter wave communication assisted by intelligent reflecting surfaces(IRS),we propose a deep learning-based channel estimation *** proposed scheme employs a hybrid active/passive IRS architecture,wherein the least square(LS)algorithm is initially utilized to acquire the channel estimate from the active ***,this estimation is interpolated to obtain a preliminary channel estimation and ultimately refined into an accurate estimate of the channel using the channel super-resolution convolutional neural network(Chan-SRCNN)deep learning *** simulation results demonstrate that the proposed scheme surpasses LS,orthogonal matching pursuit(OMP),synchronous OMP(SOMP),and deep neural network(DNN)channel estimation algorithms in terms of normalized mean squared error(NMSE)performance,thereby validating the feasibility of the proposed approach.

关键词： intelligent reflecting surface millimeter wave channel estimation deep learning

Study on the influence of curcumin on chemosensitivity of nephroblastoma cells

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Asian Pacific Journal of Tropical Medicine 2016年第8期9卷 779-782页

作者： Xiao-Yong Li Yuan-Yuan Feng Wei Dan Deng Pan Guo-Feng Zhang xian-liang wang Guang-Jun Hou Department of Pediatric Surgery Children's Hospital of Zhengzhou Department of Paediatrics Children's Hospital of Zhengzhou Department of Paediatrics Maternal and Child Health Hospital of Tonglu County

Objective:To study the influence of curcumin on chemosensitivity of nephroblastoma ***:Human nephroblastoma cells line SK-NEP-1 was transplanted to the nude mice subcutaneously to establish the implantation tumor model of human nephroblastoma cells.A total of 30 tumor-bearing mice were divided into three groups of ten *** routine chemotherapy group was given vincristine(0.05 mg/mL·0.2 mL/d) and actinomycin D(15 ng/mL·0.2 mL/d) combined chemotherapy *** curcumin chemotherapy group was given the same combined chemotherapy regimens and curcumin(30 mg/kg/d) by intraperitoneal *** control group was given normal saline(NS) of the same volume by intraperitoneal *** administration would be kept for 4 weeks and 3 days a *** volumetric changes of every group were *** serum of every group in different time was collected and the VEGF content was detected by *** mice were cercrificed and the tumor tissues were stripped and weighed after 4 weeks’ *** tumor inhibition rate was *** cell proliferation activity and apoptosis rate were detected by MTT and flow cytometry *** data were statistically analyzed by SPSS ***:The tumor volume,serum VEGF content,tumor inhibition rate,cell proliferation activity and apoptosis rate of routine chemotherapy group and curcumin chemotherapy group had significant differences comparing with the control group(P<0.05) after 4-week’s *** cancer growth of curcumin chemotherapy group was obviously decreased and even tended to shrink comparing with routine chemotherapy group(χ2=15.732,P=0.007).The cell proliferation activity was significantly reduced and the apoptosis rate was significantly higher,(χ~2=9.427,P=0.012)which showing the effect of chemotherapy was ***:The chemosensitivity of nephroblastoma cells could be improved by curcumin,then the effect of preoperative adjuvant chemotherapy scheme would be enhanced,the gro

关键词： Nephroblastoma Transplanted tumor model Curcumin Chemosensitivity Vincristine

Source,Characterization of Indoor Dust PAHs and the Health Risk on Chinese Children

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Current Medical Science 2021年第2期41卷 199-210页

作者： Xin-qi wang Xu LI Yu-yan YANG Lin FAN Xu HAN Li LI Hang LIU Tan-xi GE Li-qin SU xian-liang wang Yuan-duo ZHU China CDC Key Laboratory of Enviroment and Population Health National Instiute of Environmental HealthChinese Center for Disease Control and PreventionBeijing 100021China

Polycyclic aromatic hydrocarbons(PAHs)in indoor dust are one of the common exposure sources for children *** aim of this study is to explore PAHs pollution status in indoor dust and estimate health risk on Chinese children with big *** average concentration was used to analyze source and characterization of PAHs in indoor dust based on peer=reviewed *** to specific inclusion crteria,17 studies were included finally to analyze weighted average *** national average concentration of ∑_(16)PAHs was approximately 25.696 ug/*** highest concentration of ∑_(16)AHs was in Shanxi(2111.667 ug/g),and the lowest was in Hong Kong(1.505 μg/g).The concentrations in Shanxi and Guangdong were higher than national level and the over standard rate was 18.18%.The concentrations of individual PAHs varied greatly across the country,and Flu in Shanxi was the highest(189.400 μg/g).The sources of PAHs varied in different regions and combustion processes played a leading *** exposure through ingestion and dermal contact was more carcinogenic than *** incremental lifetime cancer risk model indicated that children lived in Shanxi were found in the highest health risk coupled with the highest BaPE concentration(54.074μg/g).Although PAHs concentrations of indoor dust showed a downward trend from 2005 to 2018,indoor environmental sanitation should be improved with multidisciplinary *** standard should be possibly established to minimize children exposure to PAHs in indoor dust in China.

关键词： indoor dust polycyclic aromatic hydrocarbons source children China health risk