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Model test of the group piles foundation of a high-speed railway bridge in mined-out area

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Frontiers of Structural and Civil Engineering 2016年第4期10卷 488-498页

作者： Xin LIANG Qian-gong chenG Jiu-jiang WU jian-ming chen Faculty of Geoseienees and Environmental Engineering Southwest Jiaotong University Chengdu 611756 China Faculty of Civil Engineering Guangxi University of Science and Technology Liuzhou 545006 China

The research on the mechanism of pile-soil-cap-goaf interaction and settlement of high-speed railway bridge located in mined-out area is still relatively rare. By taking the pile group of Guanshandi bridge foundation in Hefei- Fuzhou high-speed railway as the prototype, a model test is carried out. According to the similarity theory, the similar constant is derived and the similar model material is determined. Meanwhile, three types of data including the bearing behavior of piles, and the settlement law, and soil among piles are investigated. It can be found that： the influence of goaf on the bearing capacity of pile is inversely to the loading degree, the larger of loading degree, the smaller impact of goaf on the bearing capacity. There is no negative side friction can been found in pile body and the degree of downward tendency for the barycenter of side friction layout is obvious for piles in goaf. Although the bearing ratio of soil resistance under cap is relatively large, the cap effect is suggested be ignored considering the characteristic of goaf. There is a maximum critical value for the uneven settlement of pile group in goaf, and when the value is reached, the uneven settlement stop growing anymore. In addition, the formula for calculating bearing capacity and settlement of pile group in goaf based on test results, theory analysis and related standard is established.

关键词： high-speed railway mined-out areas goaf group piles foundation physical model test bearing capacity,settlement

Preparations of TiO_2 film coated on foam nickel substrate by sol-gel processes and its photocatalytic activity for degradation of acetaldehyde

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Journal of Environmental Sciences 2007年第1期19卷 80-85页

作者： HU Hai XIAO Wen-jun YUAN jian SHI jian-wei chen ming-xia SHANG GUAN Wen-feng Research Center for Combustion and Environment Technology Shanghai Jiao Tong University. Shanghai 200030 China

Anatase TiO2 films were successfully prepared on foam nickel substrates by sol-gel technique using tetrabutyl titanate as precursor. The characteristics of the TiO2 films were investigated by XPS, XRD, FE-SEM, TEM and UV-Vis absorption spectra. The photocatalytic activities of TiO2 films were investigated by photocatalytic degradation reactions of gaseous acetaldehyde, an indoor pollutant, under ultraviolet light irradiation. It was found that Ni^2＋ doping into TiO2 films due to the foam nickel substrates resulted in the extension of absorption edges of TiO2 films from UV region to visible light region. The pre-heating for foam nickel substrates resulted in the formation of NiO layer, which prevented effectively the injection of photogenerated electrons from TiO2 films to metal nickel. The TiO2 films displayed high photocatalytic activity for the degradation of acetaldehyde, and were enhanced by calcining the substrates and coating TiO2 films repeatedly. The high activity was mainly attributed to the improvement of the characteristics of substrate surface and the increase of active sites on photocatalyst.

关键词： photocatalyst TiO2 films foam nickel sol-gel acetaldehyde degradation

Electrochemical Properties of Poly(ethylene oxide)(PEO) Doped TiO_2-PEO Films Prepared by Sol-gel Dip Coating Technique

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Journal of Wuhan University of Technology(Materials Science) 2001年第2期16卷 6-8,12页

作者：袁坚 School of Materials Science and Eng. Wuhan University of Technology Wuhan 430070 China

PEO modified Ti02 -PEO organic-inorganic hybrid thin films were prepared via, sol-gel dipping process on glass substrate pre-coated with ITO. The preparation parameters were studied. Electrochemical and optical properties of the films were characterized by cyclic voltammetric response and visible transmittance. X-ray diffraction (XRD) was used to determined the crystalline structure of the gel. The results show the sols added with PEO have acceptable stable periods for practical use. The PEO modified optical transitivity of the hybrid films has heavy effects on the crystallization of TiO2 during structural evolution because of the interaction between PEO and Ti02 . PEO-TiO2 films have better electrochemical activity than the TiO2 equivalent behaved as higher Li + insertion/extraction current density and cyclic reversibility.

关键词： sol-gel dip-coating films electrochromic materials PEO Ti02

Establishment of a Stable PrP^(Sc) Panel from Brain Tissues of Experimental Hamsters with Scrapie Strain 263K

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Biomedical and Environmental Sciences 2009年第2期22卷 151-156页

作者： BAO-YUN ZHANG CHAN TIAN JUN HAN chen GAO QI SHI jian-ming chen HUI-YING jianG WEI ZHOU AND XIAO-PING DONG State Key Laboratory for Infectious Disease Prevention and Control National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention Beijing 100052 China

Objective To establish a stable PrP^Sc panel from brain tissues of experimental hamsters infected with scrapie agent 263K for evaluating diagnostic techniques of human and animals＇ prion diseases. Methods Thirty brain tissue samples from hamsters intracerebrally infected with scrapie strain 263K and another 30 samples from normal hamsters were selected to prepare 10%, 1%, and 0.5% brain homogenates, which were aliquoted into stocks. PrP^Sc in each brain homogenate was determined by proteinase K digestions followed by Western blot assay and partially by immunohistochemistry. Stability and glycoforms of PrP^Sc were repeatedly detected by prp^SC-specific Western blots in half a year and 3 years later. Results PrPsc signals were observed in all 10% brain homogenates of infected hamsters. Twenty out of 30 stocks and 19 out of 30 stocks were PrPsc positive in 1% and 0.5% brain homogenatesof infected hamsters, respectively. TWenty-seven out of 30 stocks presented three positive bands in 10% brain homogenates, whereas none of 1% and 0.5% homogenates contained 3 bands. The detection of prpSc-specific signals stored in half a year and 3 years later demonstrated that the ratio of PrPsc positive samples and glycoforms was almost unchanged. All normal hamsters＇ brain homogenates were PrP^Sc negative. Conclusion A PrP^Sc panel of prion disease can be established, which displays reliably stable prp^Sc-specific signals and glycoforms.

关键词： TSE prp^Sc Panel Glycoforms Stability

Intelligent geochemical interpretation of mass chromatograms:Based on convolution neural network

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Petroleum Science 2024年第2期21卷 752-764页

作者： Kai-ming Su Jun-Gang Lu jian Yu Zi-Xing Lu Shi-Jia chen Hubei Key Laboratory of Petroleum Geochemistry and Environment Wuhan430100HubeiChina College of Resources and Environment Yangtze UniversityWuhan430100HubeiChina School of Geoscience and Technology Southwest Petroleum UniversityChengdu610500SichuanChina Changqing Oilfield Company PetroChinaXi'an710021ShaanxiChina

Gas chromatography-mass spectrometry(GC-MS)is an extremely important analytical technique that is widely used in organic *** is the only approach to capture biomarker features of organic matter and provides the key evidence for oil-source correlation and thermal maturity ***,the conventional way of processing and interpreting the mass chromatogram is both timeconsuming and labor-intensive,which increases the research cost and restrains extensive applications of this *** overcome this limitation,a correlation model is developed based on the convolution neural network(CNN)to link the mass chromatogram and biomarker features of samples from the Triassic Yanchang Formation,Ordos Basin,*** this way,the mass chromatogram can be automatically *** research first performs dimensionality reduction for 15 biomarker parameters via the factor analysis and then quantifies the biomarker features using two indexes(*** and PMI)that represent the organic matter thermal maturity and parent material type,***,training,interpretation,and validation are performed multiple times using different CNN models to optimize the model structure and hyper-parameter setting,with the mass chromatogram used as the input and the obtained MI and PMI values for supervision(label).The optimized model presents high accuracy in automatically interpreting the mass chromatogram,with R2values typically above 0.85 and0.80 for the thermal maturity and parent material interpretation results,*** significance of this research is twofold:(i)developing an efficient technique for geochemical research;(ii)more importantly,demonstrating the potential of artificial intelligence in organic geochemistry and providing vital references for future related studies.

关键词： Organic geochemistry Biomarker Mass chromatographic analysis Automated interpretation Convolution neural network Machine learning

Ultrahigh spatiotemporal resolution beam signal reconstruction with bunch phase compensation

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Nuclear Science and Techniques 2024年第5期35卷 99-108页

作者： You-ming Deng Yong-Bin Leng Xing-Yi Xu jian chen Yi-Mei Zhou Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of the Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Chinese Academy of SciencesShanghai 201204China University of Science and Technology of China Hefei 230026China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

Various electromagnetic signals are excited by the beam in the acceleration and beam-diagnostic elements of a particle *** is important to obtain time-domain waveforms of these signals with high temporal resolution for research,such as the study of beam–cavity interactions and bunch-by-bunch parameter ***,a signal reconstruction algorithm with ultrahigh spatiotemporal resolution and bunch phase compensation based on equivalent sampling is proposed in this *** with traditional equivalent sampling,the use of phase compensation and setting the bunch signal zero-crossing point as the time reference can construct a more accurate reconstructed *** basic principles of the method,simulation,and experimental comparison are also *** on the beam test platform of the Shanghai Synchrotron Radiation Facility(SSRF)and the method of experimental verification,the factors that affect the reconstructed signal quality are analyzed and discussed,including the depth of the sampled data,quantization noise of analog-to-digital converter,beam transverse oscillation,and longitudinal *** results of the beam experiments show that under the user operation conditions of the SSRF,a beam excitation signal with an amplitude uncertainty of 2%can be reconstructed.

关键词： Turn-by-turn bunch phase compensation technique Equivalent sampling Signal reconstruction algorithm Ultrahigh spatiotemporal resolution SSRF

Self-adaptive gas flow and phase change behaviors during hydrate exploitation by alternate injection of N_(2) and CO_(2)

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Petroleum Science 2024年第3期21卷 2120-2129页

作者： Bo-jian Cao Yi-Fei Sun Hong-Nan chen Jin-Rong Zhong ming-Long Wang ming Wang Chang-Yu Sun Guang-Jin chen State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China School of Chemistry and Chemical Engineering Changsha University of Science&TechnologyChangsha410114HunanChina

Since hydrate resources play a part of the stratigraphic framework structure in sediments,establishing a safe and economic method for hydrates exploitation remains the primary challenge to this *** the proposed methods,the spontaneous displacement of CH_(4) from hydrate cages by CO_(2) seems to be a perfect mechanism to address gas production and CO_(2) storage,especially in today's strong demand for carbon reduction and replacing clean *** extensive lab researches,in the past decade,injecting a mixture of CO_(2) and small molecule gas has become a key means to enhance displacement efficiency and has great potential for ***,there is a lack of in-depth research on gas flow in the reservoir,while the injected gas always passes through low-saturated hydrate areas with high permeability and then occurs gas channel in a short term,finally resulting in the decreases in gas production efficiency and produced gas ***,we explored a new injection-production mode of alternate injection of N2 and CO_(2) in order to fully coordinate the advantages of N_(2) in enhanced hydrate decomposition and CO_(2) in solid storage and heat *** alternate"taking"and"storing"processes perfectly repair the problem of the gas channel,achieving self-regulation effect of CH_(4) recovery and CO_(2) *** 3-D experimental results show that compared to the mixed gas injection,CH_(4) recovery is increased by>50%and CO_(2) storage is increased by>70%.Additionally,this alternate injection mode presented a better performance in CH_(4) concentration of produced gas and showed outstanding N_(2) utilization ***,we analyzed its self-adaptive gas flow mechanism and proposed an application model of"one injection and multiple production".We look forward to this study accelerating the application of CO_(2)-CH_(4) replacement technology.

关键词： Hydrate Replacement CH_(4)recovery CO_(2)storage Reservoir remediation

Chronic subdural hematoma associated with arachnoid cyst:report of two cases

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Chinese Medical Journal 2007年第24期120卷 2339-2340页

作者： ZHANG Hong ZHANG jian-ming chen Gao Department of Neurosurgery Second Affiliated Hospital ZhejiangUniversity College of Medicine Hangzhou 310009 China

Intracranial arachnoid cysts, which often occur in children （75%）, account for 1% of intracranial *** cyst is most commonly located at the middle cranial fossa and more frequently on the left side. The disease is usually asymptomatic, but can become acutely symptomatic because of hemorrhage and cyst enlargement, which may result from minor head trauma and are often complicated with a subdural hematoma. Here we report two cases of intracranial arachnoid cyst associated with ipsilateral chronic subdural hematoma.

关键词： arachnoid cysts hematoma, subdural

Molecular Epidemiological Study on Prevalence of Human Papillomaviruses in Patients with Common Warts in Beijing Area

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Biomedical and Environmental Sciences 2009年第1期22卷 55-61页

作者： YAN-JUN LEI chen GAO chen WANG JUN HAN jian-ming chen GUANG-CAI XIANG QI SHI HUI-YING jianG WEI ZHOU RUN AN chen-FANG DONG YU-KANG YUAN XIAO-PING DONG State Key Laboratory for Infectious Disease Prevention and Control National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention Beijing 100052 China School of Medicine Xi'an Jiaotong University Xi'an 710061 Shaanxi China Department of Dermatology China-Japan Friendship Hospital Beijing 100029 China

Objective To study the circulation, distribution, and genomic diversity of HPVs in common warts in Beijing area of China. Methods Forty eight patients with pathologically diagnosed common warts were screened for the presence of HPV with HPV type-specific PCR and direct sequencing analysis. The genomic diversity of HPVs prevalent in Chinese patients was analyzed based on LCR. Results Forty one （85.5%） samples were positive for HPV DNA, 13（31.7%）-HPV-57, 12（29.3%）-HPV-la, 7（17%）-HPV-27 and 5（12.2%）-HPV-2a. Four cases were infected with two different HPV types, two （4.9%） with HPV-la and HPV-27, one （2.4%） with HPV-1 and HPV-57 and one （2.4%） with HPV-27 and HPV-57. In contrast to the prevalence of single strain of novel HPV-57 variant and HPV-1 prototype, two HPV-2 and three HPV-27 novel variants were found to circulate in Beijing. Conclusion HPV-1, -2, -27 and -57 are predominantly prevalent in patients with common warts in Beijing.

关键词： Human papillomavirus Genotype Common warts Variants