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Journal of Environmental Sciences 2008年第7期20卷 769-777页

作者： lei Bingli HUANG Shengbiao QIAO min State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

An accidental discharge of nitrobenzene happened in November 2005 in the Songhua River,*** AQUATOX model was modified and adapted to simulate the time-dependent nitrobenzene distribution in this multimedia aquatic system and its potential ecological *** concentrations in flowing water,sediment,and biota were *** on the initial concentrations of nitrobenzene observed in the field during the accidental discharge,that is,0.167-1.47 mg/L at different river segments, the predic...

关键词： nitrobenzene environmental fate ecological impact the Songhua River AQUATOX model

Thermodynamic watershed hydrological model: Constitutive relationship

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Science China(Technological Sciences) 2008年第9期51卷 1353-1369页

作者： tian FuQiang HU HePing lei ZhiDong State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China

The representative elementary watershed (REW) approach proposed by Reggiani et al. was the first attempt to develop scale adaptable equations applicable directly at the macro scale. tian et al. extended the initial definition of REW for simulating the energy related processes, and re-organized the deriving procedure of balance equations so that additional sub-regions and substances could be easily incorpo-rated. The resultant ordinary differential equation set can simulate various hydro-logical processes in a physically reasonable way. However, constitutive and geo-metric relationships have not been developed for tian et al.'s equation set, which are necessary for the thermodynamic watershed hydrological model to apply in hydrological modeling practice. In this work, the constitutive equations for mass exchange terms and momentum exchange terms were developed as well as geo-metric relationships. The closed ordinary differential equation set with nine equa-tions was finally obtained.

关键词： thermodynamics hydrological model constitutive relationship thermodynamic watershed hydrological model representative elementary watershed

Distribution function estimates by Wasserstein metric and Bernstein approximation for C^(-1) functions

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Applied Mathematics(A Journal of Chinese Universities) 2015年第2期30卷 141-150页

作者： WU Zong-min tian Zheng Shanghai Key Laboratory for Contemporary Applied Mathematics School of Mathematical SciencesFudan University

The aim of the paper is to estimate the density functions or distribution functions measured by Wasserstein metric, a typical kind of statistical distances, which is usually required in the statistical learning. Based on the classical Bernstein approximation, a scheme is presented. To get the error estimates of the scheme, the problem turns to estimating the L1 norm of the Bernstein approximation for monotone C-1 functions, which was rarely discussed in the classical approximation theory. Finally, we get a probability estimate by the statistical distance.

关键词： Wasserstein metric Bernstein approximation L1 norm approximation confidence interval

Characteristics of trace elements of the No.9 coal seam from the Anjialing mine, Ningwu coalfield, China

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Chinese Journal Of Geochemistry 2015年第3期34卷 391-400页

作者： Wang Jinxi Wang Qi tian lei Key Laboratory of Resource Exploration Research of Hebei Province Hebei University of Engineering

Trace elements of the No. 9 coal seam from Aanjialing mine were measured by ICP–MS. The results indicated that Li, Ga, Cr, Sr, Zr and Pb are significantly enriched in the No. 9 coal seam. The Li and Ga contents in most of the coal seam samples reached an economically valuable level. Most trace elements were enriched near the roof and floor. The data from the Sr/Ba, V/Zn, Th/U, V/Zr and V/Ni ratios reveal that during this period, the peat swamp from this area was formed in swamp water, which was influenced by sea-water or, in an sea-land transition environment, where the ancient water salinity was slightly high. The Eu negative anomaly obviously shows that the rare earth elements are consistent with the terrigenous rocks, so we deduced that the rare earth elements contained in the mineral may mainly come from terrestrial detritus.

关键词：微量元素特征宁武煤田煤层煤矿微量元素富集陆源碎屑岩中国 ICP-MS

Elevation spatial characteristic investigation based on 3D massive MIMO channel measurements at 6 GHz

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The Journal of China Universities of Posts and Telecommunications 2018年第3期25卷 1-7,91页

作者： Zheng Zhe tian lei Zhang Jianhua State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications

As the key technology of the 5th generation （5G）, 3-dimensional （3D） massive multi-input and multi-output （MIMO） is expected to be widely used in small cell network （SCN）. In this paper, in order to investigated the tradeoff between limited size in SCN and the capacity gain from increasing antenna elements, the spatial performances of 3D massive MIMO based on a 512×16 MIMO channel measurements at 6 GHz in urban microcell （UMi） scenario are studied. Enormous channel impulse responses （CIR） are collected and reconstructed, which enables us to present comparative results of the capacity and the eigenvalue spread （ES）. Furthermore, the impacts of antenna element number and spacing on system performance are investigated, i. e. , 32, 64, 128 elements are selected from the 512 transmitter （Tx） array with elevation interval spacing being 0.5, 1 and 2 wavelengths for each. Interestingly, the capacity gap can be obviously observed on the comparison between the 1 and 2 wavelength antenna spacing cases, which implies that correlation cannot be ignored when the antenna spacing is larger than 1 wavelength when massive antennas are equipped. The contrast results show that the capacities are enlarged with the increasing of antenna elements number, and larger antenna spacing will lead to higher channel capacity as expected. However, the capacity gains brought by the increasing of antenna spacing will descend to certain degrees as the antenna number increases. Collectively, these results will provide further insights into 3D massive MIMO utilization.

关键词： massive MIMO channel capacity eigenvalue spread elements spacing antenna number

A review of trachoma history in China: research, prevention, and control

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Science China(Life Sciences) 2016年第6期59卷 541-547页

作者： Ningli Wang Shijing Deng lei tian Beijing Institute of Ophthalmology Beijing Tongren Eye Center Beijing Tongren Hospital Capital Medical UniversityBeijing Ophthalmology & Visual Sciences Key Laboratory

Trachoma is one of the most widespread blinding eye diseases, which is harmful to human visual health. The efforts to prevent and control trachoma in China can be divided into three periods, i.e., highly epidemic period, research on pathogenesis and control of trachoma, and blinding trachoma elimination and epidemiological evaluation. In 1956, Prof. Feifan Tang and Xiaolou Zhang first discovered and isolated Chlamydia trachomatis, which clarified the cause of trachoma, and kick-started a fresh chapter in trachoma research, prevention, and control around the world. Although, the prevalence of trachoma differed in different areas, the average prevalence once exceeded 50% and was as high as 90% in some areas before and at early liberation of China. Therefore, the government-led efforts were made to comprehensively prevent and control trachoma, including development of National Plan for the Prevention and Control of Trachoma, nationwide screening and treatment of trachoma, implementation of National Patriotic Health Campaign and improvement of water supply and lavatories. After decades of effort, China reached the goal of eliminating blinding trachoma in 2015. China has gained remarkable achievements in the prevention and treatment of trachoma, making outstanding contributions toward the goal of eliminating trachoma worldwide. The research, prevention, and control of trachoma in China were reviewed in this paper.

关键词： Chlamydia Chlamydia trachomatis blinding trachoma

A shape-persistent plasticine-like conductive hydrogel with self-healing properties for peripheral nerve regeneration

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Journal of Materials Science & Technology 2023年第11期142卷 134-143页

作者： Xinchang Kang Xiaojun Li Can Liu min Cai Pengfei Guan Yian Luo Youjun Guan Yu tian Kunyu Ren Chengyun Ning lei Fan Guoxin Tan lei Zhou School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China Department of Spine Surgery Guangzhou Key Laboratory of Spine Disease Prevention and Treatmentthe Third Affiliated HospitalGuangzhou Medical UniversityGuangzhou 510150China Department of Orthopedic Surgery Nanfang HospitalSouthern Medical UniversityGuangzhou 510515China School of Materials Science and Engineering South China University of TechnologyGuangzhou 510641China Department of Orthopedic Surgery the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Hospital of Stomatology Guanghua School of StomatologyGuangdong Provincial Key Laboratory of StomatologySun Yat-sen UniversityGuangzhou 510055China Department of Pediatric Orthopedic Center for Orthopedic Surgerythe Third Affiliated Hospital of Southern Medical UniversityGuangzhou 510515China

In recent years,electrically conductive hydrogel-based nerve guidance conduits(NGCs)have yielded promising results for treating peripheral nerve injuries(PNIs).However,developed ones are generally pre-manufactured and exhibit a limited ability to achieve good contact with nerve tissue with irregu-lar ***,we developed a plasticine-like electrically conductive hydrogel consisting of gelatin,conducting polypyrrole,and tannic acid(named GPT)and assessed its ability to promote peripheral nerve *** shape-persistent GPT hydrogel exhibited good self-healing properties and could easily be molded to form a conduit that could match any injured nerve *** electrical properties could be tuned by changing the PPy *** vitro,the improved conductivity of the hydrogel pro-moted dorsal root ganglion(DRG)axonal *** importantly,we found that the GPT hydrogel enhanced axonal regeneration and remyelination in vivo,preventing denervation atrophy and enhancing functional recovery in a mice model of sciatic nerve *** results suggest that our plasticine-like NGC has huge prospects for clinical application in the repair of PNI.

关键词： Plasticine-like Conductive hydrogel Self-healing Moldability Peripheral nerve conduit

Modulation instability,rogue waves and conservation laws in higher-order nonlinear Schrodinger equation

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Communications in Theoretical Physics 2021年第2期73卷 1-10页

作者： min-Jie Dong Li-Xin tian School of Mathematical Sciences Nanjing Normal UniversityNanjingJiangsu 210023China Nonlinear Scientific Research Center Jiangsu UniversityZhenjiangJiangsu 212013China

In this paper,the modulation instability(MI),rogue waves(RWs)and conseryation laws of the coupled higher-order nonlinear Schrodinger equation are *** to MI and the 2×2 Lax pair,Darboux-dressing transformation with an asymptotic expansion method,the existence and properties of the one-,second-,and third-order RWs for the higher-order nonlinear Schrodinger equation are *** addition,the main characteristics of these solutions are discussed through some graphics,which are draw widespread attention in a variety of complex systems such as optics,Bose-Einstein condensates,capillary fow,superfluidity,fluid dynamics,and *** addition,infinitely-many conservation laws are established.

关键词： higher-order nonlinear Schrodinger equation modulation instability rogue waves conservation laws

引起敦化市手足口病流行的肠道病毒71型氨基酸位点变异分析

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中国卫生工程学 2018年第5期17卷 690-692页

作者：杨金红魏雷雷田丽敏王爽田鑫曹凤瑞程涛单元春付思美吕淑梅李大强吉林省敦化市疾病预防控制中心性病艾滋病科吉林敦化133000 吉林省疾病预防控制中心吉林省卫生厅病毒重点实验室

目的分析2009-2011年引起吉林省敦化市手足口病(HFMD)流行的肠道病毒71型(EV-A71) VP1编码区氨基酸位点的变异。方法对2009-2011年分离于敦化市HFMD病例的3株EV-A71分离株的VP1编码区进行逆转录-聚合酶链反应、核苷酸序列测定,使用MEGA ... 详细信息

目的分析2009-2011年引起吉林省敦化市手足口病(HFMD)流行的肠道病毒71型(EV-A71) VP1编码区氨基酸位点的变异。方法对2009-2011年分离于敦化市HFMD病例的3株EV-A71分离株的VP1编码区进行逆转录-聚合酶链反应、核苷酸序列测定,使用MEGA 4.0软件和Bioedit软件分析VP1编码区基因亲缘关系及氨基酸位点的变异。结果 2009-2011年敦化市3株EV-A71均属于C4a基因亚型,并且这3株病毒在VP1编码区第22位氨基酸位点均由谷氨酰胺转变为组氨酸(Q-H),与本研究中比对的2009-2011年吉林省代表株变异一致,也与2008年安徽阜阳的分离株变异一致。结论致敦化市2009-2011年HFMD流行的EV-A71已在全省其他县市传播流行,敦化市流行株有可能是从安徽阜阳直接或辗转传播所致。

关键词： HFMD 肠道病毒71型氨基酸位点变异

Study of performance of small gamma camera consisting of crystal pixel array and position sensitive photomultiplier tube

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Nuclear Science and Techniques 2005年第4期16卷 238-243页

作者： ZHU Jie LIU Shi-Tao lei Xiao-Wen YAN tian-Xin XU Zi-Zong WANG Zhao-min Department of Modern Physics University of Science and Technology of China Hefei 230026

The performance of gamma camera with NaI(Tl) array coupled with position sensitive photomultiplier tube (PSPMT) R2486 has been studied. The pixel size of NaI(Tl) crystal is 2mm×2mm and the overall dimension of the array is 48.2mm×48.2mm×5mm. There are 484 pixels in a 22×22 matrix. Because each pixel can produce a much focused light spot and restrict the spread of photons, position resolution of the gamma camera is mainly determined by pixel size. It is shown that crystal array pixel can reduce shrinkage effect and improve intrinsic position resolution greatly via restricting the spread of photons. Experimental results demonstrate that its position resolution and linearity are much improved comparing with the gamma camera using planar crystals coupled with PSPMT.

关键词：光电倍增器像素照相机 PSPMT 线性关系