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Food web structure and trophic levels in a saltwater pond sea cucumber and prawn polyculture system

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Acta Oceanologica Sinica 2016年第4期35卷 58-62页

作者： GUO Kai ZHAO wen wang Shan LIU Baozhan ZHANG Peng Key Laboratory of Hydrobiology in Liaoning Province Dalian Ocean University Offshore Environment Services Co. Ltd.

The food sources of aquacultured Apostichopus japonicus and the trophic levels of organisms in a sea cucumber（A. japonicus） and prawn（Penaeus japonica） polyculture system in a saltwater pond in Zhuanghe, Liaoning Province were examined using carbon and nitrogen stable isotopes. Across organisms, δ13C ranged from（–25.47±0.20）‰ to（–16.48±0.17）‰（mean±SD）, and δ15N ranged from（4.23±0.49）‰ to（12.44±0.09）‰. The δ13C and δ15N contents of A. japonicus, P. japonica and Fenneropenaeus chinensis were comparatively higher than those of other organisms. Values of δ13C and δ15N revealed that P. japonica, Hemigrapsus sanguineus and Neomysis japonica comprised the largest component of the diet of A. japonicus. The mean trophic level of the organisms in this saltwater pond polyculture system was（2.75±0.08）. P. japonica, A. japonicus, F. chinensis,Synechogobius hasta and Neomysis japonica were in the 3rd trophic level（2–3）; jellyfish, H. sanguineus and zooplankton were in the 2nd trophic level（1–2）; and Enteromorpha prolifera, benthic microalgae, periphyton and suspended matter primarily consisting of phytoplankton, bacteria and humus were in the primary trophic level（0–1）.

关键词： Aposticbopus japonicas Penaeus japonica stable isotopes food web structure diet composition trophic level

Simulation and prediction in laser bending of silicon sheet

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 188-193页

作者： wang Xu-yue XU Wei-xing XU wen-ji HU Ya-feng LIANG Yan-de wang Lian-ji Key Laboratory for Precision and Non-traditional Machining Technology of the Ministry of Education Dalian University of Technology Dalian 116024 China

The laser bending of single-crystal silicon sheet （0.2 mm in thickness） was investigated with JK701 Nd：YAG laser. The models were developed to describe the beam characteristics of pulsed laser. In order to simulate the process of laser bending, the FEM software ANSYS was used to predict the heat temperature and stress-strain fields. The periodic transformation of temperature field and stress-strain distribution was analyzed during pulsed laser scanning silicon sheet. The results indicate that the mechanism of pulsed laser bending silicon is a hybrid mechanism in silicon bending, rather than a simple mechanism of TGM or BM. This work also gets silicon sheet bent after scanning 6 times with pulsed laser, and its bending angle is up to 6.5°. The simulation and prediction results reach well agreement with the verifying experiments.

关键词： laser bending silicon sheet pulsed laser simulation

Pressure relief, gas drainage and deformation effects on an overlying coal seam induced by drilling an extra-thin protective coal seam

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Mining Science and Technology 2009年第6期19卷 724-729页

作者： LIU Hai-bo cheng Yuan-ping SONG Jian-cheng SHANG Zheng-jie wang Liang National Engineering Research Center for Coal ＆ Gas Control China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Zhengzhou Coal Industrial Group Corporation Ltd. Zhengzhou Henan 452371 China

Numerical simulations and field tests were used to investigate the changes in ground stress and deformation of, and gas flow from, a protected coal seam under which an extra-thin coal seam was drilled. The geological conditions were: 0.5 meter mining height, 18.5 meter coal seam spacing and a hard limestone/fine sandstone inter-stratum. For these conditions we conclude: 1) the overlying coal-rock mass bends and sinks without the appearance of a caving zone, and 2) the protected coal seam is in the bending zone and undergoes expansion deformation in the stress-relaxed area. The deformation was 12 mm and the relative defor- mation was 0.15%. As mining proceeds, deformation in the protected layer begins as compression, then becomes a rapid expansion and, finally, reaches a stable value. A large number of bed separation crannies are created in the stress-relaxed area and the permeability coefficient of the coal seam was increased 403 fold. Grid penetration boreholes were evenly drilled toward the protected coal seam to affect pressure relief and gas drainage. This made the gas pressure decrease from 0.75 to 0.15 MPa, the gas content decrease from 13 to 4.66 m3/t and the gas drainage reach 64%.

关键词： extra-thin protective coal seam drilling pressure relief expansion deformation gas drainage

A novel and efficient route for the preparation of atorvastatin

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Chinese Chemical Letters 2011年第10期22卷 1159-1162页

作者： Jian Gao Yang Hui Guo Ya Ping wang Xiang Jing wang wen Sheng Xiang Department of Biochemical Engineering Northeast Agricultural University Harbin 150030 China Zhejiang Hisun Pharmaceutical Co. Ltd. Taizhou 318000 China

A novel and efficient synthetic method of atorvastatin was *** key step of the synthesis was the construction of the olefin linkage between the chiral side chain and skeleton via a Horner-Wadsworth-Emmons reaction,resulting in the advanced intermediate of atorvastatin under hydrogenation of the olefin over Pd/*** novel method is more useful for the practical synthesis of atorvastatin than its document reported methods.

关键词： Atorvastatin Horner-Wadsworth-Emmons reaction Synthesis Intermediate

THEORY AND EXPERIMENTAL INVESTIGAION OF FLEXURAL WAVE PROPAGATION IN THIN RECTANGULAR PLATE WITH PERIODIC STRUCTURE

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Chinese Journal of Mechanical Engineering 2005年第3期18卷 385-388页

作者： wen Jihong Yu Dianlong wang Gang Zhao Hongang Liu Yaozong College of Mechatronics Engineering and Automation National University of Defense Technology Changsha 410073 China

With the idea of the phononic crystals, a thin rectangular plate with two-dimensional periodic structure is designed. Flexural wave band structures of such a plate with infinite structure are calculated with the plane-wave expansion （PWE） method, and directional band gaps are found in the ΓX direction. The acceleration frequency response in the ΓX direction of such a plate with finite structure is simulated with the finite element method and verified with a vibration experiment. The frequency ranges of sharp drops in the calculated and measured acceleration frequency response curves are in basic agreement with those in the band structures. Thin plate is a widely used component in the engineering structures. The existence of band gaps in such periodic structures gives a new idea in vibration control of thin plates.

关键词： Phononic crystals Flexural wave band gaps Thin rectangular plate

Prognostic factors and long-term outcomes of hilar cholangiocarcinoma:A single-institution experience in China

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World Journal of Gastroenterology 2016年第8期22卷 2601-2610页

作者： Hai-Jie Hu Hui Mao Anuj Shrestha Yong-Qiong Tan wen-Jie Ma Qin Yang Jun-Ke wang Nan-Sheng cheng Fu-Yu Li Department of Biliary Surgery West China Hospital of Sichuan University Department of Respiratory Medicine West China Hospital of Sichuan University Department of General Surgery Gandaki Medical College

AIM: To evaluate the prognostic factors of hilar cholangiocarcinoma in a large series of patients in a single ***: Eight hundred and fourteen patients with a diagnosis of hilar cholangiocarcinoma that were evaluated and treated between 1990 and 2014, of which 381 patients underwent curative surgery, were included in this study. Potential factors associated with overall survival(OS) and disease-free survival(DFS) were evaluated by univariate and multivariate ***: Curative surgery provided the best long-term survival with a median OS of 26.3 mo. The median DFS was 18.1 mo. Multivariate analysis showed that patients with tumor size > 3 cm [hazard ratio(HR) = 1.482, 95%CI: 1.127-1.949; P = 0.005], positive nodal disease(HR = 1.701, 95%CI: 1.346-2.149; P < 0.001), poor differentiation(HR = 2.535, 95%CI: 1.839-3.493; P < 0.001), vascular invasion(HR = 1.542, 95%CI: 1.082-2.197; P = 0.017), and positive margins(HR = 1.798, 95%CI: 1.314-2.461; P < 0.001) had poor OS outcome. The independent factors for DFS were positive nodal disease(HR = 3.383, 95%CI: 2.633-4.348; P < 0.001), poor differentiation(HR = 2.774, 95%CI: 2.012-3.823; P < 0.001), vascular invasion(HR = 2.136, 95%CI: 1.658-3.236; P < 0.001), and positive margins(HR = 1.835, 95%CI: 1.256-2.679; P < 0.001). Multiple logistic regression analysis showed that caudate lobectomy [odds ratio(OR) = 9.771, 95%CI: 4.672-20.433; P < 0.001], tumor diameter(OR = 3.772, 95%CI: 1.914-7.434; P < 0.001), surgical procedures(OR = 10.236, 95%CI: 4.738-22.116; P < 0.001), American Joint Committee On Cancer T stage(OR = 2.010, 95%CI: 1.043-3.870; P = 0.037), and vascular invasion(OR = 2.278, 95%CI: 0.997-5.207; P = 0.051) were independently associated with tumorfree margin, and surgical procedures could indirectly affect survival outcome by influencing the tumor resection margin. CONCLUSION: Tumor margin, tumor differentiation, vascular invasion, and lymph node status were independent factors for OS and DFS

关键词： Hilar cholangiocarcinoma Prognosis Surgical outcome Survival Tumor-free margin

Palladium and carbon synergistically catalyzed room-temperature hydrodeoxygenation(HDO) of vanillyl alcohol–A typical lignin model molecule

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Journal of Energy Chemistry 2017年第1期26卷 8-16页

作者： Qi wang Neeraj Gupta Guodong wen Sharifah Bee Abd Hamid Dang Sheng Su School of Materials Science and Engineering University of Science and Technology of China Institute of Metal Research Chinese Academy of Sciences Nanotechnology & Catalysis Research Centre (NANOCAT) University of Malaya IPS Building

Vanillyl alcohol, which is made up of an aromatic ring, an alcoholic hydroxyl group, a phenolic hydroxyl group and a methoxy group, was selected as the model molecule of lignin. Various carbon materials supported Pd catalysts were chosen to catalyze the HDO of vanillyl alcohol. The catalysts were characterized via TEM, TPD, XRD, XPS and CO-chemisorption. It was found that different carbon materials could obviously influence the particle sizes, dispersion and distribution of Pd or PdO particles. Palladium and carbon can synergistically catalyze the room-temperature HDO of vanillyl alcohol even at room temperature, and the carboxyl group was found to be the effective active acid site during the reaction. Possible reaction mechanism was also proposed. The existence of the effective active acid sites on the carbon supports could obviously lower the reaction temperature without decreasing the selectivity, as a result, making the production of renewable fuels by HDO much more economically feasible, which is of much importance. © 2016 Science Press

关键词： Bioconversion Carbon Catalysts Dispersions Molecules Palladium

Application of the asynchronous advantage actor–critic machine learning algorithm to real-time accelerator tuning

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Nuclear Science and Techniques 2019年第10期30卷 133-141页

作者： Yun Zou Qing-Zi Xing Bai-Chuan wang Shu-Xin Zheng cheng cheng Zhong-Ming wang Xue-Wu wang Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China Laboratory for Advanced Radiation Sources and Application Tsinghua UniversityBeijing 100084China Department of Engineering Physics Tsinghua UniversityBeijing 100084China State Key Laboratory of Intense Pulsed Radiation Simulation and Effect Northwest Institute of Nuclear TechnologyXian 710000China

This paper describes a real-time beam tuning method with an improved asynchronous advantage actor–critic(A3C)algorithm for accelerator *** operating parameters of devices are usually inconsistent with the predictions of physical designs because of errors in mechanical matching and ***,parameter optimization methods such as pointwise scanning,evolutionary algorithms(EAs),and robust conjugate direction search are widely used in beam tuning to compensate for this ***,it is difficult for them to deal with a large number of discrete local *** A3C algorithm,which has been applied in the automated control field,provides an approach for improving multi-dimensional *** A3C algorithm is introduced and improved for the real-time beam tuning code for *** in which optimization is achieved by using pointwise scanning,the genetic algorithm(one kind of EAs),and the A3C-algorithm are conducted and compared to optimize the currents of four steering magnets and two solenoids in the low-energy beam transport section(LEBT)of the Xi’an Proton Application *** currents are determined when the highest transmission of a radio frequency quadrupole(RFQ)accelerator downstream of the LEBT is *** optimal work points of the tuned accelerator were obtained with currents of 0 A,0 A,0 A,and 0.1 A,for the four steering magnets,and 107 A and 96 A for the two ***,the highest transmission of the RFQ was 91.2%.Meanwhile,the lower time required for the optimization with the A3C algorithm was successfully *** with the A3C algorithm consumed 42%and 78%less time than pointwise scanning with random initialization and pre-trained initialization of weights,respectively.

关键词： Real-time beam tuning Parameter optimization Asynchronous advantage actor–critic algorithm Low-energy beam transport

Self-assembly Behavior of Copolymers with Super Segregated Structure Containing Fluorinated Segments

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Chinese Journal of Polymer Science 2014年第7期32卷 817-817,818-822页

作者： Jin-ni Deng wen-bin wang Zhao-hui Zheng 丁小斌 Yu-xing Peng chengdu Institute of Organic Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

Copolymers with super segregated structure of hydrophilic methoxy poly（ethylene glycol）（mPEG） and fluorophilic poly（1H,1H,2H,2H-perfluorodecyl acrylate）（PFA） were prepared. And just because of this super segregated structure which was resulted from the extremely strong incompatibility between the two blocks, several interesting self- assembly behaviors of the copolymers were displayed and studied under different conditions. Transmission electron microscope （TEM） showed that with the increase of PFA in the polymerization system, the incompatibility in this super segregated structure became stronger, and the self-assembly behavior changed from ball-like or rod-like to vesicles, and finally collapsed to sheet-like. The self-assembly behavior changed likewise when the initial concentration increased. And the interesting formation of these barrel-like and spindle-like vesicles was finally studied with different cooling speeds. It＇s finally found that with this super segregation structure, these new self-assembly morphology might be formed due to the extremely strong incompatibility between mPEG and PFA segments.

关键词： Super segregated structure Self-assembly behavior Barrel-like and spindle-like vesicles.