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A new method for fluid identification and saturation calculation of low contrast tight sandstone reservoir

Petroleum Science 2024年第5期21卷 3189-3201页

作者： Shuai Wang Ran-Hong Xie Guo-wen Jin jiang-Feng Guo Li-zhi Xiao State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

The resistivity difference between oil and gas layers and the water layers in low contrast tight sandstone reservoirs is subtle. Fluid identification and saturation calculation based on conventional logging methods are facing challenges in such reservoirs. In this paper, a new method is proposed for fluid identification and saturation calculation in low contrast tight sandstone reservoirs. First, a model for calculating apparent formation water resistivity is constructed, which takes into account the influence of shale on the resistivity calculation and avoids apparent formation water resistivity abnormal *** on the distribution of the apparent formation water resistivity obtained by the new model, the water spectrum is determined for fluid identification in low contrast tight sandstone *** this, according to the average, standard deviation, and endpoints of the water spectrum, a new four-parameter model for calculating reservoir oil and gas saturation is built. The methods proposed in this paper are applied to the low contrast tight sandstone reservoirs in the Q4 formation of the X53 block and X70 block in the south of Songliao Basin, China. The results show that the water spectrum method can effectively distinguish oil-water layers and water layers in the study area. The standard deviation of the water spectrum in the oil-water layer is generally greater than that in the water layer. The new four-parameter model yields more accurate oil and gas saturation. These findings verify the effectiveness of the proposed methods.

关键词： Low contrast reservoirs Fluid identification Saturation calculation Water spectrum method Conventional logging

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Biosynthesis of the Central Piperidine Nitrogen Heterocycle in Series a Thiopeptides

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Chinese Journal of Chemistry 2019年第1期37卷 35-41页

作者： Jingyu Liu zhi Lin Hua Chen Heng Guo jiang Tao wen Liu State Key Laboratory of Bioorganic and Natural Products Chemistry Center for Excellence on Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of Sciences345 Lingling RoadShanghai 200032China Department of General Dentistry Ninth People s HospitalShanghai Jiao Tong Umversity School of MedicineShanghai Key Laboratory of 5tomatologyShanghai 200011China State Key Laboratory of Microbial Metabolism School of Life Science & BiotechnologyShanghai Jiao Tong University800 Dongchuan RoadShanghai 200240China Huzhou Center of Bio-Synthetic Innovation 1366 Hongfeng RoadHuzhouZhejiang 313000China

Summary of main observation and conclusion Thiopeptides,arising from complex posttranslational modifications of a genetically encoded precursor peptide,are of great interest due to their structural complexity and important biological *** of these antibiotics share a macrocyclic peptidyl core that contains a central,six-membered nitrogen heterocycle and are classified into five series a-e based on the oxidation state of the central nitrogenous ***,we report that the biosynthesis of the central piperidine heterocycle of series a thiopeptides relies on the activity of homologues of an F420H2-dependent reductase TppX4 by exploiting and characterizing the piperidine-containing thiopeptin biosynthetic gene (tpp)cluster in Streptomyces *** vitro reconstruction of TppX4 activity demonstrated that the piperidine heterocycle of thiopeptins was transformed from a dehydropiperidine heterocycle,and TppX4 tolerated the changes in the C-termini and macrocyclic peptidyl core of substrate and also tolerated dehyropiperidine-containing monocyclic or bicyclic *** identification of TppX4 and its substrate tolerance enriches the biosynthetic toolbox for development of additional thiopeptide analogs for clinical drug screening.

关键词： complexity important report

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REGIONAL TOURISM COOPERATION IN TRIANGLE ZONE OF LIAONING PROVINCE

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Chinese Geographical Science 2005年第4期15卷 361-367页

作者： LONG jiang-zhi School of Tourism and Hotel Management Dongbei University of Finance ＆ Economics Dalian 116025 P. R. China

Strengthening the regional tourism cooperation is the requirement of both tourism development and tourist competition drive. On the one hand, resources, products, market and infrastructure in tourism are characteristics of half-public goods, which are the externalities. On the other hand, tourism competition has evolved from individual scenic spot, or finn competition to regional competition, which also requires urgent regional tourism cooperation. In recent years, the regional economic cooperation has been becoming popular in the world. The triangle tourism zone of Liaoning Province, constituted by Shenyang, Dalian and Dandong, is the core region of Liaoning tourism system. This regional tourism cooperation has been raised for a long time, but has not made substantial progress as yet. In recent years, the strategic cooperation among them has been becoming urgent, along with the change of tourism competition models, as well as the desire for building a Northeast Asia tourist economy circle. Based on literature, this paper establishes a conceptual frame of regional tourism cooperation and applies it in the analysis of the strategic tourism cooperation of Liaoning Province＇s golden triangle zone. This paper firstly examines both qualifications and motives concerning with cooperation among the three cities, and believes that the biggest difficulties involve traditional ideas, administrative institutions, communications, economic performances, time constraints, and more overlap among their tourist markets. Then this paper continues to construct a cooperating mechanism, including participant arrangements, construction of operating mechanism and construction of assisting mechanism. At last, this paper proposes approaches to the strategic cooperation such as introducing Xiuyan County, strategic integration and developing differentiated and complemented tourism products.

关键词： regional tourism cooperation triangle tourism zone of Liaoning

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Finite Diffeomorphism Types of Four Dimensional Ricci Flow with Bounded Scalar Curvature

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Acta Mathematica Sinica,English Series 2021年第11期37卷 1751-1767页

作者： wen Shuai jiang School of Mathematical Sciences Zhejiang UniversityHangzhou 310027P.R.China

In this paper,we consider Ricci flow on four dimensional closed manifold with bounded scalar curvature,noncollasping volume and bounded *** such conditions,we can show that the manifold has finitely many diffeomorphism types,which generalizes Cheeger–Naber’s result to bounded scalar curvature along Ricci *** particular,this implies the manifold has uniform L^(2) Riemann curvature *** an application,we point out that four dimensional Ricci flow would not have uniform scalar curvature upper bound if the initial metric only satisfying lower Ricci curvature bound,lower volume bound and upper diameter bound.

关键词： Ricci flow scalar curvature

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A quantum chemistry study on reaction mechanisms of SO_2 with O_3 and H_2O_2

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第9期10卷 1327-1333页

作者： Shu-dong jiang zhi-hua WANG Jun-hu ZHOU Zheng-cheng wen Ke-fa CEN State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

Reaction mechanisms of SO2 with O3 and H2O2 were investigated using quantum chemistry ab initio methods. Structures of all reactants, products, and transition states were optimized at the B3LYP/6-311G＋（3df,2p） level, and energy calculations were made at the G2M level. SO2 reactions with O3 and H2O2 occurred by O-abstraction and OH-abstraction by SO2, respectively, at length forming SO3＋O2 （3Eg） and H2SO4. For SO2＋O3 reactions the barrier height was predicted to be 9.68 kcal/mol with a rate constant of 3.61 × 10^-23 cm^3/（molecule.s） at 300 K, which is below the experimental upper limit. The rate constant predicted for this reaction accords well with the one provided by National Institute for Standards and Technology （NIST） in 250-500 K. For SO2＋H2O2 reactions the barrier height was predicted to be 62.39 kcal/mol with a rate constant of 2.48× 10^-61 cm^3/（molecule.s） at 300 K.

关键词： Sulfur dioxide Ozone Hydrogen peroxide Reaction mechanism Rate constant Quantum chemistry

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Digital and analog hybrid control in adaptive interference cancellation system

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The Journal of China Universities of Posts and Telecommunications 2010年第6期17卷 1-10页

作者： jiang Yun-hao ZHAO zhi-hua TANG Jian LI wen-lu XIAO Huan College of Electrical and Electronic Engineering Huazhong Utliversity of Science and Technology Wuhan 430074 China National Key Laboratory for Vessel Integrated Power System Technology Naval University of Engineering Wuhan 430033 China

The digital proportion control is introduced to improve the performance of the analog adaptive interference cancellation system （ICS）. For the high frequency parts of the signals after multiplier are not required,the sampling frequency need not satisfy the sampling theorem for high frequency. Because the sampling,calculation and output expend time in digital control,the ideal condition,delay condition and delay-wait condition are taken into account. Through analyzing the system model with three conditions,we gain the stable conditions of the system,the optimization step factors that can make the system converge fastest and the formulas of the interference cancellation ratios （ICRs）. One step convergence can be accomplished under ideal condition,whereas the system can not converge in one step under delay condition and delay-wait condition. The calculation results show the convergence speed of delay-wait condition is slower than that of delay condition. The ICR is improved with the increase of the step factor which is in stable bound,but the convergence speed is decreased if the step factor exceeds the optimization step factor. In order to avoid that confine,the method of amending the steady state weight to improve the ICR is proposed. The analyses are in agreement with the computer simulations.

关键词： digital and analog hybrid control adaptive interference cancellation weight ICR convergence speed

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A New ent-Kaurane Diterpenoid from Isodon enanderianus

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Chinese Chemical Letters 2001年第8期12卷 711-712页

作者： zhi NA Bei jiang Hui YANG Zhong wen LIN Han Dong SUN Laboratory of Phytochemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650204 Chemistry Deparment of the College of Life Science and Chemistry Yunnan UniversityKunming 650091

A new spirosecokaurenoid, enanderinanin F 1 and its C-6 epimer, angustifolin were isolated from the aerial parts of Isodon enanderianus. The structure of 1 was determined on the basis of spectral data, especially by 2... 详细信息

关键词： Isodon enanderianus ent -kaurane diterpenoid enanderinanin F angustifolin

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Breeding the Mite-Resistant Honeybee by Nutritional Crossbreed Technology

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Agricultural Sciences in China 2008年第6期7卷 762-767页

作者： XIE Xian-bing PENG wen-jun ZENG zhi-jiang Honeybee Research Institute Jiangxi Agricultural University Nanchang 330045 P.R.China Institute of Apicultural Research Chinese Academy of Agricultural Sciences Beijing 100093 P.R.China Quanzhou Normal University Quanzhou 362000 P.R.China

Mite （Varroa destructor） is one of the most serious parasite threats to the honey bee （Apis mellifera） reared in China. The beekeepers mainly use the drug to control and kill the mite in the past years, but the honey products may be contaminated and the mite is becoming drug-resistant. The main idea of this paper is to research the possibility of mite-resistant honeybee rearing by nutritional crossbreed. The larvae （Apis mellifera ligustica） are bred with the royal jelly of Apis carana carana, and then the morphological index of the worker generation, genotypic frequency and gene frequency of the MDH Ⅱ, genetic resemblance, and mite resistance are measured. The results show that： compared to the parent workers, the proboscis length, anterior wing area, the total length of the third and fourth dorsal plate of the abdomen, the length of the fourth dorsal plate of the tuberculum, the area of the sixth abdominal segment, and the area of wax mirrors are significantly different, but the differences in the brachium index, dactylus index, and wing claw are not significant. Moreover, there are some mutations in the genotypic frequency and gene frequency of the MDH Ⅱ. The mite resistance of the nutritional crossbreed worker is significantly higher. The morphological, physical, and biochemical characters, genetic resemblance, and the mite-resistant ability of the worker generation can be changed by nutritional crossbreeding. Nutritional crossbreeding can be a new way to breed the honeybee.

关键词： honeybees Varroa destructor nutritional crossbreed

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铸牢中华民族共同体意识研究回溯与展望(2017—2023)——基于CiteSpace的可视化分析

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三峡大学学报（人文社会科学版） 2025年第1期47卷 29-40,56页

作者：龚志祥谭雯心东北大学秦皇岛分校民族学学院河北秦皇岛066004

本文运用CiteSpace软件绘制可视化知识图谱,分析2017—2023年中国知网CNKI核心期刊(北大核心、CSSCI期刊)铸牢中华民族共同体意识研究领域的1 772篇高质量文献,从发文量及趋势、作者及机构、引用量及高频关键词、多学科跨学科及研究机... 详细信息

本文运用CiteSpace软件绘制可视化知识图谱,分析2017—2023年中国知网CNKI核心期刊(北大核心、CSSCI期刊)铸牢中华民族共同体意识研究领域的1 772篇高质量文献,从发文量及趋势、作者及机构、引用量及高频关键词、多学科跨学科及研究机构合作等进行分析。铸牢中华民族共同体意识研究的发文量自2017年始逐年增长,经过快速上升,达到高水平的平稳增长。铸牢中华民族共同体意识理论体系研究深化仍是热点,实践研究与政策响应研究需进一步拓展和深化。

关键词：铸牢中华民族共同体意识 CiteSpace可视化分析研究现状

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A candidate protective factor in amyotrophic lateral sclerosis:heterogenous nuclear ribonucleoprotein G

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Neural Regeneration Research 2023年第7期18卷 1527-1534页

作者： Fang Yang wen-zhi Chen Shi-Shi jiang Xiao-Hua Wang Ren-Shi Xu Department of Neurology Jiangxi Provincial People’s HospitalThe Clinical College of Nanchang Medical CollegeThe First Affiliated Hospital of Nanchang Medical CollegeNanchangJiangxi ProvinceChina Department of Geriatrics and General Practice/General Family Medicine Jiangxi Provincial People’s HospitalThe Clinical College of Nanchang Medical CollegeThe First Affiliated Hospital of Nanchang Medical CollegeNanchangJiangxi ProvinceChina

Heterogenous nuclear ribonucleoprotein G is down-regulated in the spinal cord of the Tg(SOD1*G93A)1Gur(TG)amyotrophic lateral sclerosis mouse ***,most studies have only examined heterogenous nuclear ribonucleoprotein G expression in the amyotrophic lateral sclerosis model and heterogenous nuclear ribonucleoprotein G effects in amyotrophic lateral sclerosis pathogenesis such as in apoptosis are *** this study,we studied the potential mechanism of heterogenous nuclear ribonucleoprotein G in neuronal death in the spinal cord of TG and wild-type mice and examined the mechanism by which heterogenous nuclear ribonucleoprotein G induces *** nuclear ribonucleoprotein G in spinal cord was analyzed using immunohistochemistry and western blotting,and cell proliferation and proteins(TAR DNA binding protein 43,superoxide dismutase 1,and Bax)were detected by the Cell Counting Kit-8 and western blot analysis in heterogenous nuclear ribonucleoprotein G siRNA-transfected PC12 *** analyzed heterogenous nuclear ribonucleoprotein G distribution in spinal cord in the amyotrophic lateral sclerosis model at various time points and the expressions of apoptosis and proliferation-related *** nuclear ribonucleoprotein G was mainly localized in *** lateral sclerosis mice were examined at three stages:preonset(60-70 days),onset(90-100 days)and progression(120-130 days).The number of heterogenous nuclear ribonucleoprotein G-positive cells was significantly higher in the anterior horn of the lumbar spinal cord segment of TG mice at the preonset stage than that of control group but lower than that of the control group at the onset *** number of heterogenous nuclear ribonucleoprotein G-positive cells in both central canal and surrounding gray matter of the whole spinal cord of TG mice at the onset stage was significantly lower than that in the control group,whereas that of the lumbar spinal cord segment of TG mice was

关键词： amyotrophic lateral sclerosis Bax heterogenous nuclear ribonucleoprotein G heterogenous nuclear ribonucleoprotein G-siRNA neuron death superoxide dismutase 1 TAR DNA binding protein 43 TG(SOD1*G93A)1Gur mice

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