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Quantitative Estimation on Methane Storage Capacity of Organic-Rich Shales from the Lower Silurian Longmaxi Formation in the Eastern Sichuan Basin, China

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Journal of Earth Science 2023年第6期34卷 1851-1860页

作者： Xiaowen Guo Tao Luo Tian Dong Rui Yang Yuanjia Han Jizheng Yi sheng he Zhiguo Shu Hanyong Bao Key Laboratory of Tectonics and Petroleum Resources Ministry of EducationChina University of GeosciencesWuhan 430074China Jianghan Oilfield Branch Company SINOPECWuhan 430223China

The assessment of gas storage capacity is crucial to furthering shale gas exploration and development in the eastern Sichuan Basin,*** organic-rich shale samples were selected to carry out the high pressure methane sorption,low-pressure N_(2)/CO_(2) gas adsorption,and bulk and skeletal density measurements to investigate the methane storage capacity(MSC).Based on the relative content of clay,carbonates,quartz+feldspar,we grouped the 11 samples into three lithofacies:silica-rich argillaceous shale(CM-1),argillaceous/siliceous mixed shale(M-2),and clay-rich siliceous shale(S-3).The total porosity of the shale samples varies from 3.4% to 5.6%,and gas saturation ranges from 47% to 89%.The measured total gas amount ranges from 1.84 mg/g to 4.22 mg/g with the ratio of free gas to total gas amount ranging from 52.7% to 70.8%.Free gas with high content in the eastern Sichuan Basin may be the key factor controlling amount of shale gas *** TOC content critically controls the MSC of shales,because micropore,mesopore volumes and the specific surface areas associated with organic matter provide the storage sites for the free and adsorbed *** methane sorption capacities of samples from different lithofacies are also affected by clay minerals and moisture *** minerals can provide additional surface areas for methane sorption,and water can cause a 7.1%-42.8% loss of methane sorption *** total porosity,gas-bearing porosity,water saturation,free gas and adsorbed gas number of samples from different lithofacies show subtle differences if the shale samples had similar TOC *** results suggest that,in the eastern Sichuan Basin,clay-rich shale lithofacies is also prospecting targets for shale gas production.

关键词： methane shale gas Longmaxi Formation Sichuan Basin

Forest gaps regulate seed germination rate and radicle growth of an endangered plant species in a subtropical natural forest

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Plant Diversity 2022年第5期44卷 445-454页

作者： Jing Zhu Lan Jiang De-Huang Zhu Cong Xing Meng-Ran Jin Jin-Fu Liu Zhong-sheng he Key Laboratory of Fujian Universities for Ecology and Resource Statistics College of ForestryFujian Agriculture and Forestry UniversityFuzhou350002China College of Ecology and Resources Engineering Wuyi UniversityWuyishanFujian354300China

The survival rate of Castanopsis kawakamii from seed to seedling is relatively low,leading to difficulties in the regeneration of its natural *** gaps play a vital role in plant regeneration and biodiversity maintenance in forest ***,our understanding of the effects of gap size and within-gap position on the seed germination and radicle growth of *** is still *** particular,our knowledge on the relationship between gap size and environmental factors and their influence on seed germination and radicle growth is *** the present study,we studied the influences of forest gaps and within-gap position on seed regeneration on the germination and radicle growth of an endangered species *** in a subtropical natural forest in *** selected three large gaps(LG,gap size above 200 m^(2)),three medium gaps(MG,gap size 50-100 m^(2)),three small gaps(SG,gap size 30-50 m^(2)),and non-gap(NG),and planted the seeds of *** in five positions within each *** results showed that(1)the influence of forest gaps on seed germination rate was,from highest to lowest,medium gaps(51%),non-gap(47%),small gaps(40%)and large gaps(17%),and the seed germination rate was the highest in all positions in medium gaps,with the exception of the east position.(2)Radicle length in forest gaps was,from highest to lowest,medium gaps,small gaps,large gaps and non-gap,and it was the highest in the east,south,west and north positions of medium gaps.(3)Canopy openness(gap size)and air temperature were the main factors influencing seed germination and radicle growth of *** concluded that medium-sized gaps were the most suitable for seed germination and radicle growth of ***,and they promote the regeneration of this endangered species in the investigated natural forest.

关键词： Forest gap Within-gap position Seed germination Radicle growth Castanopsis kawakamii

Quantitative analysis of intestinal gas in patients with acute pancreatitis

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hepatobiliary & Pancreatic Diseases International 2012年第3期11卷 314-318页

作者： Ying Liu and he-sheng Luo Department of Gastroenterology, Renmin Hospital, Wuhan University, Wuhan 430060, China Department of Gastroenterology Renmin Hospital Wuhan University Wuhan 430060 China

BACKGROUND: Disturbance of gastrointestinal function is a common complication in the early phase of acute pancreatitis (AP). Intestinal gas may reflect the function of the gut. Using plain abdominal radiographs, we investigated whether intestinal gas volume is related to AP. METHODS: Plain abdominal radiographs of 68 patients with AP within 24 hours after admission and 21 normal controls were digitized and transmitted to a computer. The region of intestinal gas was identified by an image manipulation software and the gas volume score (GVS) was calculated. The relationships between the GVS values and various clinical factors of AP were analyzed. RESULTS: The GVS in the AP group was 0.084±0.016, in the mild AP (MAP) group 0.070±0.005, and in the severe AP (SAP) group 0.094±0.013; all values were higher than that in the control group (Phe GVS in the SAP group was higher than that in the MAP group. The GVSs were correlated to the Ranson’s scores (r=0.762, Phe acute physiology and chronic health evaluation II (APAChe II) scores (r=0.801, Phe GVS in patients with secondary pancreatic and/or peripancreatic infection was 0.107±0.014, higher than that in patients without secondary infection (Phe II score and secondary pancreatic and/or peripancreatic infection. GVS may be a new prognostic tool for assessing the severity of AP in the early course of the disease.

关键词： acute pancreatitis gas volume score intestinal gas gut motility bacterial overgrowth

Design and fabrication of ultrasmall arrayed waveguide grating multiplexers based on Si nanowire waveguides

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Optoelectronics Letters 2007年第1期3卷 7-9页

作者： DAI Dao-xin LIU Liu ZheN sheng he Sai-ling Center for Optical and Electromagnetic Research State Key Lab. for Modern Optical Instrumentation Zhejiang University and Joint Research Center of Photonics of the Royal Institute of Technology（Sweden）＆ Zhejiang University （China） Hangzhon 310058 China

The large refractive index difference between Si and SiO2 makes it possible to realize ultrasmall photonic integrated circuits. A 5×5 ultracompact arrayed waveguide grating multiplexer based on 500×250 nm Si nanowire waveguides is designed and fabricated by using the technologies of E-beam writing and amorphous-Si deposition. The mea- sured channel spacing is about 1.5 nm (close to the design value) and the channel crosstalk is about –8 dB.

关键词：超小阵列波导光栅波分复用器硅纳米线波导设计制造

Increased risk of colorectal neoplasia in inflammatory bowel disease patients with post-inflammatory polyps:A systematic review and meta-analysis

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World Journal of Gastrointestinal Oncology 2022年第1期14卷 348-361页

作者： De-Gao he Xi-Jie Chen Juan-Ni Huang Jun-Guo Chen Min-Yi Lv Tian-Ze Huang Ping Lan Xiao-sheng he Department of Colorectal Surgery The Sixth Affiliated HospitalSun Yat-sen UniversityGuangdong Institute of GastroenterologyGuangdong Provincial Key Laboratory of Colorectal and Pelvic Floor DiseasesGuangzhou 510655Guangdong ProvinceChina Department of Geriatrics the first Affiliated HospitalGuangzhou Medical UniversityGuangzhou 510120Guangdong ProvinceChina

BACKGROUND Inflammatory bowel disease(IBD)patients with post-inflammatory polyps(PIPs)may carry an increased risk of colorectal neoplasia(CRN)including dysplasia and *** guidelines recommend active colonoscopy follow-up for these ***,the evidence for guidelines is still *** addition,some recent high-quality reports present a different view,which challenges the current *** hypothesize that IBD patients with PIPs are at increased risk of *** To evaluate the risk of CRN in IBD patients with and without *** A systematic search of PubMed,Embase,Cochrane Library,and Web of Science was performed to identify studies that compared the risk of CRN in IBD patients with and without *** addition,we screened the reference lists and citation indices of the included *** assessment was performed using the Newcastle–Ottawa *** odds ratio(OR)was calculated using the random-effects model to explore the final pooled effect size of the included studies and determine whether PIPs increase the risk of *** analysis,subgroup analysis,and assessment of publication bias were performed to examine the sources of *** Twelve studies with 5819 IBD patients,including 1281(22.01%)with PIPs,were considered eligible for this *** found that IBD patients with PIPs were at an increased risk of CRN as compared to those without PIPs[OR 2.01;95%confidence interval(CI):1.43–2.83].The results were similar when colorectal cancer was used as the study endpoint(OR 2.57;95%CI:1.69–3.91).Furthermore,the risk of CRN was still increased(OR 1.80;95%CI:1.12–2.91)when restricted to ulcerative colitis *** was high among the included studies(I^(2)=75%).Subgroup analysis revealed that the high heterogeneity was due to the study *** analysis showed that the main statistical outcomes did not essentially change after excluding any one of the included *** significant pu

关键词： Colorectal neoplasia Inflammatory bowel disease Ulcerative colitis Postinflammatory polyps Pseudopolyps Meta-analysis

Main Mechanism for Generating Overpressure in the Paleogene Source Rock Series of the Chezhen Depression,Bohai Bay Basin, China

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Journal of Earth Science 2019年第4期30卷 775-787页

作者： Junli Zhang sheng he Yuqin Wang Yongshi Wang Xuefeng Hao shengyuan Luo Ping Li Xuewei Dang Ruizhi Yang Key Laboratory of Tectonics and Petroleum Resources Ministry of EducationChina University of GeosciencesWuhan 430074China Research Institute of Exploration and Development Shengli Oilfield CompanySINOPECDongying 257000China Wuhan Center of China Geological Survey Wuhan 430205China Wuhan Zondy Cyber-Tech Co. Ltd. Wuhan 430074China

The Chezhen depression,located in the south of Bohai Bay Basin,is an oil-producing basin in China. The third and fourth members of the Shahejie Formation(E(s3) and E(s4)) are the main source rock series in the Chezhen depression. Widespread overpressures occurred in the E(s3) and E(s4) from the depths of approximately 2 000 to 4 600 m,with the maximum pressure coefficient of 1.98 from drillstem tests(DST). Among the sonic,resistivity and density logs,sonic-log is the only reliable pressure indicator and can be used to predict the pore pressure with Eaton's method. All the overpressured mudstones in the source rock series have higher acoustic traveltimes compared with normally pressured mudstones at a given depth. The overpressured mudstones in the E(s3) and E(s4) units are characterized by a normal geothermal gradient,high average density values up to 2.5 g/cm^3,strong present-day hydrocarbon generation capability,abundant mature organic matter and high contents of residual hydrocarbons estimated by the Rock-Eval S1 values and chloroform-soluble bitumen "A" values. All suggest that the dominant mechanism for overpressure in the mudstones of source rock series in the Chezhen depression is hydrocarbon generation. A comparison between the matrix porosity of the normally pressured sandstones and overpressured sandstones,the quantitative evaluation of porosity loss caused by compaction and the conventional thin section inspection demonstrate that the sandstones in the Chezhen depression were normally compacted. The high contents of hydrocarbons in the overpressured reservoirs prove that the overpressure in the sandstones of the source rock series was caused by pressure transmission from the source rocks.

关键词： overpressure-generating mechanism source rock series Es3 and Es4 formations Chezhen depression

Silt Erosion Characteristics of a Cr_3C_2-NiCr Coating Fabricated by High Velocity Oxy-Fuel (HVOF) Thermal Spray

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稀有金属材料与工程 2012年第S1期41卷 453-455页

作者： Wang Qian,Wu Yuping,Li Gaiye,Guo Wenmin,he Zhihua,Hong sheng Hohai University,Nanjing 210098,China Hohai Univ Coll Mech & Mat Nanjing 210098 Jiangsu Peoples R China

A Cr3C2-NiCr coating was prepared by high velocity oxy-fuel(HVOF)thermal spray on 1Cr18Ni9Ti stainless *** and microstructures of the coating were investigated by X-ray diffraction(XRD),optical microscopy(OM)and scanning election microscopy(SEM),*** cavitation erosion resistance and silt erosion resistance of the coating were evaluated using a GB/T6383-2009 standard method in two experimental conditions(fresh water and water contained fine silt),compared with the coatings hydro machine material 1Cr18Ni9Ti stainless *** coating shows a layered structure and has a significantly higher microhardness(11.97 GPa)than that of the 1Cr18Ni9Ti stainless steel(2.1 GPa),which results in less mass losses both in cavitation erosion and silt erosion *** HVOF coating has a predominant performance in the cavitation erosion and silt erosion *** higher microhardness of the coating is the main cause which results in a less mass losses in the erosion *** the mass loss usually happens at the edges of the pores.

关键词： Cr3C2-NiCr coating cavitation erosion silt erosion

Multifactorial analysis of recurrence of cholecystolithiasis in Shanghai area

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World Journal of Gastroenterology 1999年第1期5卷 36-38页

作者： CheN Pei, WANG Bing sheng and he Lian Qi

AIM To explore the risk factors of gallbladder stone recurrence. METHODS A multifactorial analysis was made for 1058 patients in Shanghai area whose gallbladder stones disappeared after different kinds of nonsurgical therapy, including oral litholytic therapy, extracorporeal shock wave lithotripsy and percutaneous choledocholithotripsy. Serum level of insulin and total bile acid were determined in 122 patients. RESULTS After 1 8 8 years of follow up, the recurrence rate of gallbladder stone was 11 6%, 22 4%, 29 5%, 36 4%, 39 3% and 39 7% respectively within 1, 2, 3, 4, 5 and over 5 years. The risk factors for the recurrence are: primary multiple gallstones ( P he recurrence of cholecystolithiasis is related to overintake of high fat and high cholesterol food, and might also be related to low level of serum insulin.

关键词： cholecystolithiasis/therapy recurrence follow up studies

Soil respiration is driven by fine root biomass along a forest chronosequence in subtropical China

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Journal of Plant Ecology 2017年第1期10卷 36-46页

作者： Chao Wang Yinlei Ma Stefan Trogisch Yuanyuan Huang Yan Geng Michael Scherer-Lorenzen Jin-sheng he Department of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University5 Yiheyuan RoadBeijing 100871China Department for Geobotany Institute of Biology/Geobotany and Botanical GardenMartin-Luther-University Halle-WittenbergAm Kirchtor 1Halle(Saale)D-06108Germany German Centre for Integrative Biodiversity Research(iDiv)Halle-Jena-Leipzig Deutscher Platz 5eLeipzig D-04103Germany Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences12 Zhongguancun South StreetBeijing 100081China Faculty of Biology/Geobotany University of Freiburg79104 FreiburgGermany

Aims Soil respiration(Rs)is a major process controlling soil carbon loss in forest ***,the underlying mechanisms leading to variation in Rs along forest successional gradients are not well *** this study,we investigated the effects of biotic and abiotic factors on Rs along a forest successional gradient in southeast *** We selected 16 plots stratified by forest age,ranging from 20 to 120 *** each plot,six shallow collars and six deep collars were permanently inserted into the *** and deep collars were used to measure Rs and heterotrophic respiration(Rh),*** soil respiration(Ra)was estimated as the difference between Rs and *** layer respiration(R_(L))was calculated by subtracting soil respiration measured in collars without leaf litter layer(R_(NL))from *** was measured every 2 months,and soil temperature(ST)and soil volumetric water content(SVWC)were recorded every hour for 19 *** calculated daily Rs using an exponential model dependent on *** Rs was summed to obtain cumulative annual Rs *** equation modelling(SEM)was applied to identify the drivers of Rs during forest *** Findings Rs showed significant differences among three successive stages,and it was the highest in the young *** was higher in the young stage than in the medium *** annual Rs and Ra peaked in the young and old stages,*** annual Rh and respiration measured from soil organic matter(R_(SOM))decreased,whereas R_(L)increased with forest *** SEM revealed that cumulative annual Rs was influenced by fine root biomass and *** results indicated that the dominant force regulating Rs on a seasonal scale is ST;however,on a successional scale,belowground carbon emerges as the dominant influential factor.

关键词： forest succession soil respiration fine root biomass soil temperature