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Experimental studies on rock failure mechanisms under impact load by single polycrystalline diamond compact cutter

Petroleum Science 2023年第5期20卷 3100-3109页

作者： Zhao-Sheng Ji jin-bao jiang Huai-Zhong Shi Bang-Min Li Drilling Engineering Technology Research Institute Sinopec Zhongyuan Petroleum Engineering CompanyPuyangHenan457001China State Key Laboratory of Petroleum Resources and Prospecting Beijing102249China

Percussive drilling shows excellent potential for promoting the rate of penetration(ROP)in drilling hard *** diamond compact(PDC)bits account for most of the footage drilled in the oil and gas *** reveal the rock failure mechanisms under the impact load by PDC bits,a series of drop tests with a single PDC cutter were conducted to four kinds of rocks at different back rake angles,drop heights,drop mass,and drop *** the morphology characteristics of the craters were obtained and quantified by using a three-dimensional *** fracture micrographs can be observed by using scanning electron microscope(SEM).The distribution and propagation process of subsurface cracks were captured in rock-like silica glass by a high-speed photography *** results can indicate that percussive drilling has a higher efficiency and ROP when the rock fractures in brittle *** failure mode of rock is related with the type of rock,the impact speed,and the back rake angle of the *** the penetration depth and fragmentation volume get the maximum values at a back rake angle of about 45°.Increasing the weight and speed of falling hammer is beneficial to improving the rock breaking effects and *** subsurface cracks under the impact load by a single PDC cutter is shaped like a clamshell,and its size is much larger than the crater *** findings can help to shed light on the rock failure mechanisms under the impact of load by a single PDC cutter and provide a theoretical explanation for better field application of percussive drilling.

关键词： Percussive drilling PDC cutter Drop test Failure mechanism Subsurface cracks

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中学教师组织支持感对工作压力的预测作用研究

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数学的实践与认识 2017年第5期47卷 63-71页

作者：汤金宝江可申南京航空航天大学经济与管理学院江苏南京210016

在中、高考指挥棒的引导下,目前中学教师群体的工作压力达到了前所未有的高度,而教师对组织支持的感知影响着教师对工作压力的认识.通过对2187名中学教师进行问卷调查,运用SPSS和AMOS软件对数据进行分析,分析中学教师组织支持感工作压... 详细信息

在中、高考指挥棒的引导下,目前中学教师群体的工作压力达到了前所未有的高度,而教师对组织支持的感知影响着教师对工作压力的认识.通过对2187名中学教师进行问卷调查,运用SPSS和AMOS软件对数据进行分析,分析中学教师组织支持感工作压力所在水平,目前组织支持感水平处于中等状态,且教师对组织支持感的认识比较一致.中学教师工作压力总体比较高,但不同的教师群体工作压力不同.并对组织支持感预测工作压力模型进行检验.发现组织支持感与工作压力呈负相关初/高中在0.001水平上差异显著,而性别、公/民办和教龄在0.05水平上差异显著.

关键词：中学教师组织支持感工作压力

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The gut-eye axis:from brain neurodegenerative diseases to age-related macular degeneration

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Neural Regeneration Research 2025年第10期20卷 2741-2757页

作者： Qianzi jin Suyu Wang Yujia Yao Qin jiang Keran Li Department of Ophthalmology The Affiliated Eye Hospital of Nanjing Medical UniversityNanjingJiangsu ProvinceChina The Fourth School of Clinical Medicine Nanjing Medical UniversityNanjingJiangsu ProvinceChina

Age-related macular degeneration is a serious neurodegenerative disease of the retina that significantly impacts ***,the specific pathogenesis remains unclear,and effective early treatment options are consequently *** microbiome is defined as a large ecosystem of microorganisms living within and coexisting with a *** intestinal microbiome undergoes dynamic changes owing to age,diet,genetics,and other *** dysregulation of the intestinal flora can disrupt the microecological balance,resulting in immunological and metabolic dysfunction in the host,and affecting the development of many *** recent decades,significant evidence has indicated that the intestinal flora also influences systems outside of the digestive tract,including the ***,several studies have demonstrated the critical role of the gut-brain axis in the development of brain neurodegenerative diseases,including Alzheimer’s disease and Parkinson’s ***,the role of the“gut-eye axis”has been confirmed to play a role in the pathogenesis of many ocular ***,age-related macular degeneration and many brain neurodegenerative diseases have been shown to share several risk factors and to exhibit comparable *** such,the intestinal flora may play an important role in age-related macular *** the above context,the present review aims to clarify the gut-brain and gut-eye connections,assess the effect of intestinal flora and metabolites on age-related macular degeneration,and identify potential diagnostic markers and therapeutic ***,direct research on the role of intestinal flora in age-related macular degeneration is still relatively limited,while studies focusing solely on intestinal flora are insufficient to fully elucidate its functional role in age-related macular ***-on-a-chip technology has shown promise in clarifying the gut-eye interactions,while integrating analysis of the inte

关键词： age-related macular degeneration biological agents blinding eye disease dietary nutrition fecal microbial transplantation gut-eye axis intestinal flora metabolite microecology neurodegenerative disease

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CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

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Journal of Energy Chemistry 2025年第01期 522-532页

作者： jin-Peng Wang Guo-Cui Mao Hui-Lin jiang bao-Xia Dong Yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

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Maternal and fetal death associated with acute pancreatitis during pregnancy:A case report

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World Journal of Clinical Cases 2025年第10期13卷 53-58页

作者： jin Li Qing-Yan Zhang Mei-Hong Zhang Shan-Yun jiang Department of Anesthesiology Kaihua County People’s HospitalQuzhou 324300Zhejiang ProvinceChina Center for Clinical Inspection and Quarantine Kaihua County Center for Clinical Inspection and QuarantineQuzhou 324300Zhejiang ProvinceChina

BACKGROUND Acute pancreatitis in pregnancy is a rare but serious condition that can lead to high maternal mortality and fetal *** of pregnancy complicated by severe acute pancreatitis,particularly with subsequent respiratory and cardiac arrest,are rarely *** SUMMARY We present the case of a 35-year-old woman,at 36+5 weeks of gestation,who presented with paroxysmal epigastric pain accompanied by low back pain,nausea,and *** to the clinical symptoms,B-ultrasound imaging and biochemical indicators,the patient was diagnosed with acute pancreatitis and initially managed ***,3 hours after admission,the patient experienced respiratory and cardiac arrest,and the fetus *** this case,the adverse outcomes occurred due to the lack of aggressive fluid resuscitation and an active surgical *** Implementing aggressive fluid resuscitation to sustain tissue perfusion,alongside the proactive evaluation of pharmacological agents that suppress gastric acid secretion and inhibit pancreatic enzyme activity,may be beneficial in mitigating the risk of a severely adverse *** management of acute pancreatitis during pregnancy requires careful timing of surgical intervention,a thorough evaluation of the risks and benefits regarding the continuation or termination of pregnancy,and a focus on safeguarding both maternal and fetal health.

关键词： Severe acute pancreatitis Pregnancy Cardiac arrest Fetal death Case report

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Integrating lipidomics and gut microbiota to study the anti-hyperlipidemia effect of Sargentodoxae Caulis extract

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Traditional Medicine Research 2025年第1期10卷 1-11页

作者： Xiao-Xiao Zhang Li Jia Xiu-Jun Zhan Charity Ngina Qing-Rui Zhang Xiao-Ge Li Qi-bao jiang Shi Bai Miao-Miao jiang National Key Laboratory of Chinese Medicine Modernization Tianjin University of Traditional Chinese MedicineTianjin 301617China Haihe Laboratory of Modern Chinese Medicine Tianjin 301617China School of Medicine Taizhou UniversityTaizhou 318000China.

Background:Sargentodoxae Caulis(SC)is the vine stem of Sargentodoxa Cuneata(Oliv.)Rehd.&*** in ***,and it in traditional Chinese medicine has been known for promoting blood circulation and removing blood stasis as recorded in the ancient book“Illustrated Classics of Materia Medica”.It has been used effectively to treat blood stasis too in modern clinical ***,the anti-hyperlipidemia effect of SC is not fully *** paper aims at exploring the use of SC stems to improve the balance of blood lipids in the body,and its new role in treating ***:The effects of SC extract on hyperlipidemia were explored by combining lipidomics and gut ***,we explored the potential mechanism of SC in treating hyperlipidemia by pathway ***:The results showed that the stem extract of SC could restore the physiological and biochemical indices of hyperlipidemia in mice,as well as repair the morphological and structural damage to *** to the Model group,the SC extract significantly reduced the liver index,epididymal fat index,and Lee’s *** also significantly decreased serum levels of total cholesterol,triglycerides,low-density lipoprotein cholesterol,peroxisome proliferator-activated receptor gamma(PPAR-γ),D-lactate,and free fatty acids,while significantly increasing the relative content of peroxisome proliferator-activated receptor alpha(PPAR-α).These changes were statistically ***-targeted lipidomics,based on LC-MS,were utilized to investigate the lipid metabolism characteristics in serum,liver,and epididymal fat of the *** was observed that,compared to the blank group,the Model group exhibited significant changes primarily in glycerol lipids and *** treatment group also displayed alterations in these lipids.A total of 38,81,and 27 differential lipids were identified in serum,liver,and epididymal fat samples,*** these,14 common differenti

关键词： hyperlipidemia Sargentodoxae Caulis lipidomics intestinal flora

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Effects of ultrasonic-assisted extraction on bioactive compounds,volatile flavors and antioxidant activities of vine tea water extracts

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Traditional Medicine Research 2025年第1期10卷 73-81页

作者： Xiao-Long Zhou Wei-jin jiang Ji Yu Mao-Jun Yao Yun-Tong Li Hunan Provincial Key Laboratory of Research Resource Mining and High-valued Utilization on Edible&Medicinal PlantCollege of Chemistry and Chemical EngineeringJishou UniversityJishou 416000China Hunan Gaoge Dairy Co. Ltd.Changsha 410000China

Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in *** vine tea processing,a large amount of broken tea is produced,which has low commercial ***:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea ***:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid *** chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted ***,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE *** vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant ***:The findings suggest that extraction methods signi

关键词： vine tea dihydromyricetin ultrasonic-assisted extraction volatile aroma components

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Spinless Excitons Implicit in SO(5) Theory

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Communications in Theoretical Physics 2001年第11期36卷 623-624页

作者： jiang Yong-jin TAO Rui-bao Surface Physics Laboratory Fudan UniversityShanghai 200433China Surface Physics LaboratoryFudan UniversityShanghai 200433China CCAST (World Laboratory) P.O.Box 8730Beijing 100080China

A pair of up-down operators are constructed explicitly for ***'s SO(5) theory of high Tc *** them two good quantum numbers are *** up-down operators are related to the spin-independent excitons which are not considere... 详细信息

关键词： high Tc superconductivity,SO(5) theory,Lie algebra,spinless exciton

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Spin injection in a ferromagnet/resonant tunneling diode heterostructure

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Journal of University of Science and Technology Beijing 2008年第5期15卷 638-643页

作者： jin bao Fang Wan Yu Wang Xiaoguang Xu Yong jiang School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The spin transport property of a ferromagnet （FM）/insulator （Ⅰ）/resonant tunneling diode （RTD） heterostructure was studied. The transmission coefficient and spin polarization in a multilayered heterostructure was calculated by a Schrdinger wave equation. An Airy function formalism approach was used to solve this equation. Based on the transfer matrix approach,the transmittivity of the structure was determined as a function of the Feimi energy and other parameters. The result shows that the spin polarization induced by the structure oscillates with the increasing Fermi energy of the FM layer. While the thickness of the RTD is reduced,the resonant peaks become broad. In the heterostructure,the spin polarization reaches as high as 40% and can be easily controlled by the external bias voltage.

关键词： spin injection resonant tunneling diode heterostructure spin polarization

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谈轿车车身涂装·涂料的欧美、日本两大体系与工艺设计

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中国涂料 2017年第8期32卷 17-22页

作者：王锡春李文刚宫金宝蒋小平中国一汽股份有限公司长春130011 常州市骠马涂装系统工程有限公司江苏常州213000

介绍和评价了我国轿车车身涂装形成的欧美、日本两大体系格局的共同点和差别,以及发展趋势和节能减排绿化涂装工艺技术的发展动向,供同行在涂装工艺设计、消化引进技术再创新和汽车涂装绿化创新、转型升级等工作中参考。

关键词：汽车涂装·涂料体系滚浸式输送机干式漆雾铺集装置涂装工艺设计绿化创新转型升级

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