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Petroleum Science 2020年第4期17卷 1101-1118页

作者： Cong Lu Yun-Xiao Lu jian-chun guo Li-ming Liu State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China Sinopec Shengli Petroleum Engineering Co. Ltd.Underground Operation CompanyDongying 257077China PetroChina Sichuan-Chongqing Shale Gas Front Command Chengdu 610056China

Unconventional hydrocarbon reservoirs in layered formations,such as tight sandstones and shales,are continually being *** fracturing is a critical technology for the high-efficiency development of hydrocarbon *** the stress field and stability of the formation interface is vital to understanding stress propagation,preferably before the growing hydraulic fracture contacts the formation *** this study,models are developed for computing the stress field of hydraulic fracture propagation near the formation interface,and the stress fields within and at the two sides of the formation interface are *** failure modes of the interface under the impact of hydraulic fracture propagation in its vicinity are identified,and the corresponding failure criteria are *** simulating the magnitude and direction of peak stress at different parameters,the failure mode and stability of the formation interface are *** reveal that when the interface strength is weak,the formation interface fails before the growing hydraulic fracture contacts it,and its stability is significantly related to a variety of factors,including the type of formation interface,rock mechanical properties,far-field stress,structural parameters,distance between the hydraulic fracture and formation interface,and fracturing execution parameters.

关键词： Formation interface Fracture propagation Stress field Failure criterion Stability

Computation model of proppant embedment depth based on dimensional analysis

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Journal of Coal Science & Engineering(China) 2013年第4期19卷 483-487页

作者： Cong LU jian-chun guo State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Chengdu 610500China

Hydraulic fracturing is designed to form a high-conductivity fracture. The proppant will embed into the formation rock, especially in soft rock, owing to the interaction between proppant and fracture surface after fracture closure. Proppant embedment would reduce the fracture width and then lower the fracture conductivity. According to dimensional analysis, the rock is assumed to be an elastic material. Using the theory of elasticity to describe the stage of elastic deformation and analysis of the corresponding simplified embedding process, the study establish the static computation model of the two-dimensional infinite half plane and three-dimensional infinite half space model of the proppant embedment. According to laboratory results, the calculation model was modified, got an effective correction factor and analyzed the causes of errors, then discussed the factors which have impact on proppant embedment. The result calculated by the model in this paper can be reference of prop- pant optimization in on-site fracturing for a certainty degree.

关键词： proppant embedment dimension theory of elasticity experiment model

Advances in low-field nuclear magnetic resonance(NMR) technologies applied for characterization of pore space inside rocks:a critical review

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Petroleum Science 2020年第5期17卷 1281-1297页

作者： jian-chun guo Hang-Yu Zhou Jie Zeng Kun-Jie Wang Jie Lai Yu-Xuan Liu State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China Department of Chemical Engineering School of EngineeringThe University of Western Australia35 Stirling HighwayPerthWA 6009Australia Downhole Operation Branch Southwest Petroleum Engineering Co.LtdSinopecDeyang 618014China

NMR serves as an important technique for probing rock pore space,such as pore structure characterization,fluid identification,and petrophysical property testing,due to the reusability of cores,convenience in sample processing,and time efficiency in laboratory *** practice,NMR signal collection is normally achieved through polarized nuclei relaxation which releases crucial relaxation messages for result *** impetus of this work is to help engineers and researchers with petroleum background obtain new insights into NMR principals and extend existing methodologies for characterization of unconventional *** article first gives a brief description of the development history of relaxation theories and models for porous ***,the widely used NMR techniques for characterizing petrophysical properties and pore structures are ***,limitations and deficiencies of them are ***,future work on improving these insufficiencies and approaches of enhancement applicability for NMR technologies are discussed.

关键词： Low-field NMR Critical review Relaxation theory Unconventional formation

The Roles of acyI-CoA： Diacylglycerol Acyltransferase 2 Genes in the Biosynthesis of Triacylglycerols by the Green Algae Chlamydomonas reinhardtii

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Molecular Plant 2012年第4期5卷 945-947页

作者： Xiao-Dong Deng Bo Gu Ya-Jun Li Xin-Wen Hu jian-chun guo Xiao-Wen Fei Key Laboratory of Biology and Genetic Resources of Tropical Crops Ministry of AgricultureInstitute of Tropical Bioscience and BiotechnologyChinese Academy of Tropical Agricultural ScienceHaikou 571101China Department of Biochemistry Hainan Medical CollegeHaikou571101China College of Agronomy Hainan UniversityHaikou571101China

Dear Editor, Triacylglycerols （triglycerides）（TAGs）, as the major storage forms of energy, mainly are stored in adipocytes, myocytes, enterocytes, hepatocytes, and mammary epithelial cells in mammals, oilseeds in plants, and lipid droplets in microorgan- isms （Yen et al., 2008）. Aside from energy storage, TAGs have essential functions in multiple physiological processes. In plants, TAGs are crucial for seed oil accumulation, germina- tion, and seedling development （Zhang et al., 2005, 2009）. Notably, TAGs derived from plants and microorganisms could serve as the feedstock for biofuels production （Deng et al., 2009）. Therefore, understanding of the molecular basis of TAGs bio- synthesis and storage is of considerable economic importance.

关键词： biosynthesis TAGGING Lipid Droplets Microbes plants breast epithelium cell Physiological Processes Storage Diacylglycerol O-Acyltransferase Chlamydomonas reinhardtii aluminium Triglycerides Chlorophyceae

Ideal Bi‑Based Hybrid Anode Material for Ultrafast Charging of Sodium‑Ion Batteries at Extremely Low Temperatures

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Nano-Micro Letters 2025年第3期17卷 152-167页

作者： Jie Bai jian Hui Jia Yu Wang chun Cheng Yang Qing jiang Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022People’s Republic of China

Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or ***,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely ***,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock *** a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1)at 2 A g^(−1))at−60℃,outperforming all reported SIB anode *** with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1)at−40°*** on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.

关键词： Bi nanoparticles High temperature shock High-rate activation Ultrafast charging Low-temperature sodium-ion batteries

聚焦光束合金化工艺对合金化层成型及显微组织的影响

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中国激光 2003年第12期30卷 1124-1128页

作者：丁建春单际国任家烈清华大学机械工程系北京100084

采用Cr,Ni单质粉末及B ,Si造渣剂以聚焦光束合金化方法在 4 5 # 钢表面合成了奥氏体型表面层。借助扫描电镜 (SEM) ,能谱仪 (EDS) ,X射线等方法研究了合金化工艺对合金化层的成型、显微组织及物相组成的影响规律。试验结果表明 ,当合金... 详细信息

采用Cr,Ni单质粉末及B ,Si造渣剂以聚焦光束合金化方法在 4 5 # 钢表面合成了奥氏体型表面层。借助扫描电镜 (SEM) ,能谱仪 (EDS) ,X射线等方法研究了合金化工艺对合金化层的成型、显微组织及物相组成的影响规律。试验结果表明 ,当合金化元素加入量一定时 ,合金化层的成型及其显微组织不仅取决于热输入量 ,还与造渣元素B ,Si的加入量有关。为获得成型良好的合金化层 ,热输入量增加时必须提高造渣元素B ,Si的加入量。采用低热输入合成的合金化层的显微组织由大量的γ(Fe ,Ni)及少量的晶界α(Fe Cr)构成 ,而高热输入合成的合金化层中的γ(Fe ,Ni)晶界为γ(Fe ,Ni) +Cr2

关键词：激光技术光束合金化热输入造渣剂微观组织

The cGAS-STING-interferon regulatory factor 7 pathway regulates neuroinflammation in Parkinson's disease

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Neural Regeneration Research 2025年第8期20卷 2361-2372页

作者： Shengyang Zhou Ting Li Wei Zhang jian Wu Hui Hong Wei Quan Xinyu Qiao chun Cui Chenmeng Qiao Weijiang Zhao Yanqin Shen Laboratory of Neurodegenerative and Neuroinjury Diseases Wuxi Medicine SchoolJiangnan UniversityWuxiJiangsu ProvinceChina

Interferon regulatory factor 7 plays a crucial role in the innate immune ***,whether interferon regulatory factor 7-mediated signaling contributes to Parkinson's disease remains *** we report that interferon regulatory factor 7 is markedly up-regulated in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of Parkinson's disease and co-localizes with microglial *** the selective cyclic guanosine monophosphate adenosine monophosphate synthase inhibitor RU.521 and the stimulator of interferon genes inhibitor H151 effectively suppressed interferon regulatory factor 7 activation in BV2 microglia exposed to 1-methyl-4-phenylpyridinium and inhibited transformation of mouse BV2 microglia into the neurotoxic M1 *** addition,si RNA-mediated knockdown of interferon regulatory factor 7 expression in BV2 microglia reduced the expression of inducible nitric oxide synthase,tumor necrosis factorα,CD16,CD32,and CD86 and increased the expression of the anti-inflammatory markers ARG1 and *** together,our findings indicate that the cyclic guanosine monophosphate adenosine monophosphate synthase-stimulator of interferon genes-interferon regulatory factor 7 pathway plays a crucial role in the pathogenesis of Parkinson's disease.

关键词： cyclic guanosine monophosphate adenosine monophosphate synthase H151 interferon regulatory factor 7 M1 phenotype neurodegenerative disease neuroinflammation Parkinson’s disease RU521 STING type I interferon

液相色谱-串联质谱法快速测定蔬菜中19种农药残留

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分析科学学报 2017年第1期33卷 116-120页

作者：万建春郭平祝建新占春瑞左海根江西出入境检验检疫局检验检疫综合技术中心江西南昌330038

建立了蔬菜中19种农药残留的快速测定方法。蔬菜样品用乙腈-甲酸均质提取,经三氯甲烷液-液萃取,溶剂转换后加入甲苯作为保护剂;经N-丙基乙二胺(PSA)、石墨化碳黑(GCB)净化,液相色谱-串联质谱(LC-MS/MS)正离子源(ESI+)、多反应监测模式(M... 详细信息

建立了蔬菜中19种农药残留的快速测定方法。蔬菜样品用乙腈-甲酸均质提取,经三氯甲烷液-液萃取,溶剂转换后加入甲苯作为保护剂;经N-丙基乙二胺(PSA)、石墨化碳黑(GCB)净化,液相色谱-串联质谱(LC-MS/MS)正离子源(ESI+)、多反应监测模式(MRM)测定,基质匹配标准工作曲线定量。蔬菜样品基质在50~1 000ng/mL浓度范围内线性关系良好(r2>0.99)。在0.01、0.02、0.04mg/kg添加浓度水平下,各农药回收率在65.4%~120.0%之间,相对标准偏差(RSD)在3.35%~17.46%之间。实验发现QuEChERS各吸附剂对极性和化学结构不同农药的吸附作用有所不同,进一步通过正交试验设计的优化,得到了一组极性有差异和化学结构不同的农药净化用吸附剂和保护剂的组合方式。

关键词：蔬菜农药残留液相色谱-串联质谱法正交试验设计

深层页岩体积压裂缝网动态渗透率模型及其应用

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天然气地球科学 2021年第7期32卷 941-949页

作者：曾凡辉张涛马磊郭建春曾波油气藏地质及开发工程国家重点实验室西南石油大学四川成都610500 中海石油(中国)有限公司湛江分公司广东湛江524000 中国石油西南油气田公司页岩气研究院四川成都610500

深层页岩具有闭合应力高、非均质性强、流动性差等特点,体积压裂是提高深层页岩产能的重要手段。为表征体积压裂改造区非均质缝网形态及其渗透率动态变化,通过CT扫描人工造缝岩心得到二值化图像并计算分形维数,利用蒙特卡洛随机建模并... 详细信息

深层页岩具有闭合应力高、非均质性强、流动性差等特点,体积压裂是提高深层页岩产能的重要手段。为表征体积压裂改造区非均质缝网形态及其渗透率动态变化,通过CT扫描人工造缝岩心得到二值化图像并计算分形维数,利用蒙特卡洛随机建模并统计裂缝参数,基于流量等效原理分解非均质缝网。耦合页岩气黏性流、克努森扩散、表面扩散建立单缝流量方程,通过分形理论尺度升级并结合缝宽动态变化特征,建立了非均质缝网动态表观渗透率模型。结果表明:①小尺度缝网表面扩散在地层压力大于10 MPa时可忽略,黏性流比重与地层压力成正比,克努森扩散相反;②大尺度缝网克努森扩散随地层压力增加,先增大后减小,表面扩散和黏性流呈此消彼长的趋势,小尺度缝网渗透率随地层压力增加先减小后增大,大尺度缝网渗透率与地层压力成正比;③最小缝宽(bmin=10-7 m)不变时,最大缝宽增大10倍,缝网渗透率增大100倍,缝网渗透率与缝宽呈正比;④最大缝宽(bmax=10-4 m)不变时,小尺度缝网渗透率低压(5 MPa)时略大于大尺度,最小缝宽对渗透率影响不大;⑤裂缝孔隙度越大,缝网分布越密集,渗透率越高。研究成果对缝网改造区的渗流特征以及不同压力、缝网尺度下渗流机理研究具有指导意义。

关键词：深层页岩体积压裂缝网描述分形理论流量等效原理动态渗透率

Ni-catalyzed cross-electrophile alkyl-alkyl coupling reactions

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Science China Chemistry 2025年

作者： Li-Xu You Lan Tian chun-Ling guo Shun-Xi Li Yu-Cheng Liu Yu-Long Li Wei Shu College of Chemistry and Environmental Engineering Key Laboratory of Green Catalysis of Higher Education Institutes of Sichuan Sichuan University of Science and Engineering Guangming Advanced Research Institute Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology

Introducing saturated carbon-carbon bonds into organic molecules significantly increases the three-dimensional configuration,thus altering the physical and chemical properties as well as the functions of molecules. Transition-metal-catalyzed carboncarbon cross-couplings represent one of the most straightforward, efficient and modular alternatives to build saturation in a single step. However, the efficient construction of alkyl-alkyl bonds remains a formidable challenge due to the precise manipulation of multiple alkyl metallic intermediates as well as associated competitive side reactions and selectivity control. Over the past years, Ni-catalyzed cross-coupling under reductive conditions has gained more and more attention for alkyl-alkyl crosscoupling partially attributing to the low-valent state of metal centers under reducing conditions, which suppresses the competitive β-hydride elimination process, thus facilitating the formation of alkyl-alkyl bonds. In this review, the initiative and progress of Ni-catalyzed cross-electrophile alkyl-alkyl cross-coupling, including the efforts in racemic and enantioselective formation of alkyl-alkyl bonds, have been summarized and discussed. Moreover, the challenges and further opportunities in this area have also been discussed.

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