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Formation Characteristics of CO_(2) Hydrates in the Presence of Porous Media and NaCl

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 168-177页

作者： han Jianchao Zhu Shuai Gui xia College of Chemical Engineering Nanjing Tech UniversityNanjing 211816China

Hydrate-based CO_(2) sequestration is an effective method for reducing the greenhouse effect,and the presence of porous media and NaCl can impact the formation characteristics of *** study uses the constant volume temperature search method to investigate the effects of quartz sand particle size(0.006‒0.03 mm),water saturation(30%–90%),and NaCl concentration(1%‒9%)on the phase equilibrium and kinetics of CO_(2) hydrates within a temperature range of 273‒285 K and pressure range of 1.0‒3.5 *** results indicate that a decrease in quartz sand particle size or an increase in NaCl concentration shifts the hydrate phase equilibrium curve towards lower temperatures and higher pressures,making hydrate generation conditions more *** different particle size systems,there are no significant changes in the rate of CO_(2) hydrate formation or conversion *** highest hydrate conversion rate of 71.1%is observed in a 0.015 mm particle size *** increasing water saturation,both the generation rate and conversion rate of CO_(2) hydrates show a trend of first increasing and then ***,low concentrations of NaCl(1%–3%)are found to enhance the formation and conversion rates of CO_(2) ***,as NaCl concentration increases,the rate of CO_(2) hydrate formation and conversion rate decrease.

关键词： CO_(2)hydrate porous medium NaCl formation characteristics

Somatic Embryogenesis and Plant Regeneration from Two Recalcitrant Genotypes of Gossypium hirsutum L.

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Agricultural Sciences in China 2006年第5期5卷 323-329页

作者： WANG Yan-xia WANG Xing-fen MA Zhi-ying ZhanG Gui-yin han Gai-ying Hebei Agricultural University/Key Laboratory of Crop Germplasm Resources of Hebei Baoding 071001 P.R. China

An improved protocol has been developed for somatic embryogenesis and plant regeneration of recalcitrant cotton cultivars. High callus frequencies and embryogenic tissue were developed in MSB medium supplemented with gradient concentrations of KT and 2,4-D, their concentration decreasing from 0.1 to 0.01 mg·L^-1. Somatic embryos were successfully incubated in 1/2 macronutrient MSB suspension supplemented with 0.5 g· L^-1 glutamine and 0.5 g·L^-1 asparagine. Decrease in macronutrient concentration of MSB significantly alleviated browning and was beneficial to suspension cells. Transformation of somatic embryos into plants was induced in MSB medium supplemented with 3% sucrose, 0.5 g·L^-1 glutamine, 0.5 g·L^-1 asparagine, and 6.0 g·L^-1 agar. The effect of sucrose as carbohydrate was better than that of glucose for plant germination. Using this protocol, regenerated plantlets from the CCRI521 and Zhongzhi86-6 reached to as much as 19.6 and 18.5% somatic embryos, respectively.

关键词： Gossypium hirsutum L. recalcitrant genotypes plant regeneration somatic embryogenesis effect of macronutrients suspension culture

Decatungstate Incorporated Metal-organic Framework for Degradation of Rhodamine B under Sunlight Irradiation

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Chinese Journal of Structural Chemistry 2013年第12期32卷 1897-1903页

作者： LI Jie HUANG Yuan han Qiu-xia Institute of Molecular and Crystal Engineering Basic Experiment Teaching CenterHenan University Environmental Monitoring Bureau Henan University

A new decatungstate incorporated metal-organic framework {[Co2（bpdo）5（H2O）n- W10O32]}n·nbpdo·2nH2O（1, bpdo = 4,4＇-bis（pyridine-N-oxide） has been synthesized through a one-step hydrothermal reaction and characterized by elemental analyses, IR, solid UV-vis absorption spectra, and single-crystal X-ray diffraction. The structural analysis indicates that 1 displays a one-dimensional ladder structure with [W10O32]4- as guest incorporated by electrostatic interaction. The photocatalytic property of the framework toward a rhodamine B （RhB） solution was also investigated. The results indicated that compound 1 possesses high photocatalytic activity in heterogeneous system under sunlight irradiated.

关键词： polyoxometalate heterogenous catalyst decatungstate photocatalyst

Cavitation Behavior during Superplastic Deformation of AZ31 Magnesium Alloy

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Journal of Materials Science & Technology 2005年第4期21卷 510-514页

作者： Kaifeng ZhanG Deliang yin Guofeng WANG Wenbo han School of Materials Science and Engineering Harbin Institute of TechonologyHarbin 150001China

Superplasticity of AZ31 Mg alloy at the temperature range of 250-450℃ and stain rate range of 0.7×10^-3- 1.4×10^-1s^-1 was examined through uniaxial tensile *** microscopy （OM）and scanning electrom microscopy （SEM）were employed to investigate the morphology of cavities and surface relief near fracture surface,*** is shown that AZ31 Mg alloy starts to exhibit superplasticity for 300℃.The maximum elongation of 362.5% was obtained at 400℃ and strain rate of 0.7×10^-3s^-1,There exist many O-shaped cavities and filaments at the boundaries near fracture surface,The fracture of filaments results in intergranular cavity and the model for the formation of intergranular cavities is proposed .The growth of cavities is plasticity-controlled and the serrated boundaries of intergranular cavities agree with the results of surface relieves.

关键词： AZ31 magnesium alloy Superplasticity Intergranular cavity Filament

Microstructure Variation of Cold Deformed MP159 Alloy during Aging

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Journal of Materials Science & Technology 1996年第2期12卷 109-113页

作者： han, GW Feng, D yin, M Yang, NS Central Iron and Steel Research Institute Beijing 100081 China

By comparing the relationship of room temperature yield strength with the reduction of cold rolled MP159 alloy before and after aging at 650 degrees C, and by means of TEM examination on the corresponding microstructures, the occurrence of fcc(alpha)-->hcp(epsilon) martensitic transition in MP159 alloy during cold deformation and the variation of the platelet epsilon phase during aging have been studied. The results show that the platelet a phase is really formed when the cold deformation reaches a critical value, and both the amount and the width of the platelet epsilon phase would further increase during 650 degrees C aging. The increases of the amount and the width of the platelet epsilon phase result in an additional increase of yield strength. Therefore, it is concluded that the additional hardening effect of MP159 alloy after aging is not only from the precipitation of Ni(3)X disperse phase but also from the volume fraction increase of the platelet epsilon phase. Further occurrence of the martensitic transition during aging may be due to the elimination of residual compression stress within matrix induced by the fcc(alpha)-->hcp(epsilon) transition during cold deformation.

关键词： Cobalt alloys

Cross-Ice Acoustic Communication:Cascade Acoustic Channel Model and Experimental Results

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China Communications 2021年第2期18卷 228-240页

作者： Jingwei yin Wei Men Guangping Zhu xiao han Acoustic science and Technology laboratory Harbin Engineering UniversityHarbin 150001China Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001China College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China

Cross-ice acoustic information transmission is an effective means of communication in polar sea areas covered by ***,the channel is extremely complicated because of the combined influence of water,ice,and *** on the normalmode theory,this paper establishes a cascade acoustic channel(CAC)model for the transmission of underwater acoustic waves across ice *** model can calculate the displacement response of the ice layer’s upper surface by separating the upward waves from normal modes in the water and multiplying it by a transmission coefficient *** relationship between the displacement response of the upper surface of ice layer and the acoustic frequency is calculated by the finite-element method,and the calculation result was consistent with that of the CAC *** verify the applicability of the model,a cross-ice acoustic communication experiment was conducted in Songhua River in January *** results show the energy of the acoustic signals received by geophones is closely related to sound frequency and crossice acoustic communication is *** result of present research is important for understanding crossice acoustic channel characteristics and developing future cross-ice acoustic communication in polar sea areas.

关键词： cross-ice acoustic communication normal mode CAC model transmission coefficient

VAECGAN:a generating framework for long-term prediction in multivariate time series

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Cybersecurity 2021年第1期4卷 337-348页

作者： xiang yin Yanni han Zhen Xu Jie Liu Institute of Information Engineering Chinese Academy of SciencesSchool of Cyber SecurityUniversity of Chinese Academy of SciencesBeijingChina Institute of Information Engineering Chinese Academy of SciencesBeijingChina Network information department China Mobile Communications Group Co.LtdBeijingChina

Long-term prediction is still a difficult problem in data *** usually use various kinds of methods of Recurrent Neural Network to ***,with the increase of the prediction step,the accuracy of prediction decreases *** order to improve the accuracy of long-term prediction,we propose a framework Variational Auto-Encoder Conditional Generative Adversarial Network(VAECGAN).Our model is divided into three *** first part is the encoder net,which can encode the exogenous sequence into latent space vectors and fully save the information carried by the exogenous *** second part is the generator net which is responsible for generating prediction *** the third part,the discriminator net is used to classify and feedback,adjust data generation and improve prediction ***,extensive empirical studies tested with five real-world datasets(NASDAQ,SML,Energy,EEG,KDDCUP)demonstrate the effectiveness and robustness of our proposed approach.

关键词： Long-term prediction Multivariate time series Attention mechanism Generating framework

Antiviral effect of Chinese medicine jiaweisinisan in hepatitis B virus transgenic mice

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World Journal of Gastroenterology 2006年第14期12卷 2280-2283页

作者： xiao-yin Chen Guang-Dong Tong Fang xia Department of Traditional Chinese Medicine Medical College Jinan University Guangzhou 510632 Guangdong Province China Department of Gastroenterology Shenzhen Traditional Chinese Medical Hospital Shenzhen 518000 Guangdong Province China

AIM： To study the antiviral effect of Chinese medicine jiaweisinisan （JWSNS） on hepatitis B virus （HBV） infection in transgenic mice （TGM）. METHODS： Twenty two 6-8 wk old HBV TGM in the third generation were divided into TGM control group and TGM treated group randomly. The normal control group included ten normal BC 57L/6 mice at the same age. The mice in treated group were administrated with JWSNS at the concentration of 4 g/mL and the dosage of 50 g/kg per d for 30 d, while the mice in TGM control group and normal control group were administrated with normal saline at the same dosage and the same time. Polymerase chain reaction （PCR） was used to assess the contents of HBV DNA in serum of HBV TGM before and after treatments, whereas blot hybridization was utilized to measure the contents of HBV DNA in the liver of both HBV TGM and normal BC 57L/6 mice. RESULTS： The levels of serum HBV DNA in TGM treated group were remarkably decreased after the treatment of JWSNS （7.662±0.78 vs 5.22±3.14, P〈0.05）, while there was no obvious change after administration of normal saline in TGM control group （7.125±4.26 vs 8.932 ± 5.12, P〉 0.05）. The OD values of HBV DNA in the livers of the mice in TGM treated group were significantly lower than those of TGM control group （0.274±0.096 vs 0.432 ± 0.119, P 〈 0.01）. CONCLUSION： JWSNS exerts suppressive effects on HBV DNA in the serum and liver of TGM.

关键词： Traditional Chinese herbs Hepatitis B virus Transgenic mice PCR Blot hybridization Chronic hepatitis B

Power duality for multi-antenna OFDM system in broadcast channel with user scheduling

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 215-224页

作者： Feng SHE han-wen LUO Lei CHEN Hua xia Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China Datang Microelectronics Technology Co. Ltd. Beijing 100083 China

This paper deals with design and analysis of user scheduling and power allocation for multi-antenna OFDM systems with DPC,ZF-DPC,ZF-BF and TDMA transmit *** consider the general multi-user downlink scheduling problem and power minimization with multi-user rate *** to the channel state,it is shown that there is a power optimal policy which selects a subset of users in each scheduling *** present user selection algorithms for DPC,ZF-DPC,ZF-BF and TDMA for multi-antenna OFDM system in broadcast channels,and we also present the practical water-filling solution in this *** the selected users with the consideration of fairness,we derive the power optimization algorithm with multi-user rate *** also analyze the power duality of uplink-downlink for the transmit strategies of DPC,ZF-DPC and *** results show that the present user-scheduling algorithm and power minimization algorithm can achieve good power performance,and that the scheduling algorithm can guarantee fairness.

关键词： Multiple-input multiple-output (MIMO) Orthogonal frequency division multiplexing (OFDM) Broadcast channel Multi-user diversity Dirty paper coding (DPC) Downlink scheduling