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益母草碱调节GAS6/Axl信号通路对冠心病大鼠心肌损伤的影响
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作者 孟王桃 崔冬玲 +2 位作者 吴冬景 陈超 张颖颖 《中国药房》 北大核心 2025年第1期51-56,共6页
目的探讨益母草碱对生长停滞特异性蛋白6(GAS6)/酪氨酸蛋白激酶受体(Axl)信号通路的影响,阐明其减轻冠心病大鼠心肌损伤的机制。方法构建冠心病大鼠模型,将造模成功的大鼠按随机抽样方法分为模型组,益母草碱低、高剂量组(分别灌胃25、10... 目的探讨益母草碱对生长停滞特异性蛋白6(GAS6)/酪氨酸蛋白激酶受体(Axl)信号通路的影响,阐明其减轻冠心病大鼠心肌损伤的机制。方法构建冠心病大鼠模型,将造模成功的大鼠按随机抽样方法分为模型组,益母草碱低、高剂量组(分别灌胃25、100 mg/kg益母草碱+腹腔注射75 mg/kg生理盐水),益母草碱高剂量+GAS6/Axl信号通路抑制剂组(灌胃100 mg/kg益母草碱+腹腔注射75 mg/kg的R428),每组12只;另取12只正常大鼠作对照组。各给药组大鼠给予相应药物,对照组和模型组大鼠灌胃并腹腔注射等体积生理盐水,每天1次,连续48 d。给药结束后,检测大鼠心功能和血清中炎症因子及心肌损伤标志物水平;观察其心肌组织病理形态;检测其心肌组织细胞凋亡率和心肌组织中凋亡及GAS6/Axl信号通路相关蛋白表达。结果与对照组比较,模型组大鼠出现心肌细胞与心肌纤维排列紊乱、心肌细胞肥大、细胞核固缩等病变,左室射血分数、左室短轴缩短率、二尖瓣环舒张早期与舒张晚期运动速度之比及GAS6蛋白相对表达量和B细胞淋巴瘤2/B细胞淋巴瘤2相关X蛋白、磷酸化Axl/Axl比值均显著降低(P<0.05),肿瘤坏死因子α、白细胞介素1β、白细胞介素6、肌酸激酶同工酶、肌钙蛋白Ⅰ、肌红蛋白水平以及心肌组织细胞凋亡率和剪切型胱天蛋白酶3/胱天蛋白酶3比值均显著升高(P<0.05);益母草碱各剂量组大鼠上述病理情况及各检测指标均显著改善(P<0.05),且益母草碱高剂量组效果较益母草碱低剂量组明显(P<0.05);R428处理可逆转高剂量益母草碱对冠心病大鼠心肌损伤的改善作用(P<0.05)。结论益母草碱可减轻冠心病大鼠心肌损伤,其作用机制可能与激活GAS6/Axl信号通路相关。 展开更多
关键词 益母草碱 gas6/Axl信号通路 冠心病 心肌损伤
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Gas concentration pre-warning system based on fuzzy structured element
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作者 任志玲 于群 《Journal of Coal Science & Engineering(China)》 2008年第4期581-584,共4页
In order to accurately test gas concentration and effectively pre-waming when the gas concentration over-limited on work face, used the high-performance and low prices SCM and the low-cost and high transfer efficiency... In order to accurately test gas concentration and effectively pre-waming when the gas concentration over-limited on work face, used the high-performance and low prices SCM and the low-cost and high transfer efficiency bluetooth technology to forecast the gas concentration in real time. The data tested by SCM, then got the corresponding mathematical model of the data. Put forward the idea of using fuzzy structured element theory to dynamic forecast the gas concentration, analyzed the features in abnormal-effusing on work face and judge whether there was the possibility of abnormal gas-effusion. Simulation results show that mathematical model of this system about gas concentration is correct. This system changes coal mine monitoring system's traditional way of after-alarming into early-warning, and thus enhances its feasibility. 展开更多
关键词 gas concentration pre-warning structured element MONITORING
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Ammonia-induced CuO/13X for H_(2)S removal from simulated blast furnace gas at low temperature
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作者 Erping Cao Yuhua Zheng +6 位作者 Hao Zhang Jianshan Wang Yuran Li Tingyu Zhu Zhan-guo Zhang Guangwen Xu Yanbin Cui 《Green Energy & Environment》 SCIE EI CAS 2025年第1期139-149,共11页
Blast furnace gas(BFG)is an important by-product energy for the iron and steel industry and has been widely used for heating or electricity generation.However,the undesirable contaminants in BFG(especially H_(2)S)gene... Blast furnace gas(BFG)is an important by-product energy for the iron and steel industry and has been widely used for heating or electricity generation.However,the undesirable contaminants in BFG(especially H_(2)S)generate harmful environmental emissions.The desulfurization of BFG is urgent for integrated steel plants due to the stringent ultra-low emission standards.Compared with other desulfurization materials,zeolite-based adsorbents represent a viable option with low costs and long service life.In this study,an ammonia-induced CuO modified 13X adsorbent(NH_(3)–CuO/13X)was prepared for H_(2)S removal from simulated BFG at low temperature.The XRD,H_(2)-TPR and TEM analysis proved that smaller CuO particles were formed and the dispersion of Cu on the surface of 13X zeolite was improved via the induction of ammonia.Evaluation on H_(2)S adsorption performance of the adsorbent was carried out using simulated BFG,and the results showed that NH_(3)–CuO/13X-3 has better breakthrough sulfur capacity,which was more than twice the sulfur capacity of CuO/13X.It is proposed that the enhanced desulfurization performance of NH_(3)–CuO/13X is attributed to an abundant pore of 13X,and combined action of 13X and CuO.This work provided an effective way to improve the sulfur capacity of zeolite-based adsorbents via impregnation method by ammonia induction. 展开更多
关键词 Blast furnace gas DESULFURIZATION Ammonia-induced CUO 13X zeolite
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Smart Gas Sensors:Recent Developments and Future Prospective
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作者 Boyang Zong Shufang Wu +3 位作者 Yuehong Yang Qiuju Li Tian Tao Shun Mao 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期55-86,共32页
Gas sensor is an indispensable part of modern society withwide applications in environmental monitoring,healthcare,food industry,public safety,etc.With the development of sensor technology,wireless communication,smart... Gas sensor is an indispensable part of modern society withwide applications in environmental monitoring,healthcare,food industry,public safety,etc.With the development of sensor technology,wireless communication,smart monitoring terminal,cloud storage/computing technology,and artificial intelligence,smart gas sensors represent the future of gassensing due to their merits of real-time multifunctional monitoring,earlywarning function,and intelligent and automated feature.Various electronicand optoelectronic gas sensors have been developed for high-performancesmart gas analysis.With the development of smart terminals and the maturityof integrated technology,flexible and wearable gas sensors play an increasingrole in gas analysis.This review highlights recent advances of smart gassensors in diverse applications.The structural components and fundamentalprinciples of electronic and optoelectronic gas sensors are described,andflexible and wearable gas sensor devices are highlighted.Moreover,sensorarray with artificial intelligence algorithms and smart gas sensors in“Internet of Things”paradigm are introduced.Finally,the challengesand perspectives of smart gas sensors are discussed regarding the future need of gas sensors for smart city and healthy living. 展开更多
关键词 Smart gas sensor Electronic sensor Optoelectronic sensor Flexible and wearable sensor Artificial intelligence
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Removal of elemental mercury from coal combustion flue gas by sodium halides impregnated red mud
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作者 MUHAMMAD Sarfraz LI Yang +3 位作者 YANG He JIN Lijun LI Dekang HU Haoquan 《燃料化学学报(中英文)》 北大核心 2025年第1期53-69,共17页
Mercury removal from coal combustion flue gas remains a significant challenge for environmental protection due to the lack of cost-effective sorbents.In this study,a series of red mud(RM)-based sorbents impregnated wi... Mercury removal from coal combustion flue gas remains a significant challenge for environmental protection due to the lack of cost-effective sorbents.In this study,a series of red mud(RM)-based sorbents impregnated with sodium halides(NaBr and NaI)are presented to capture elemental mercury(Hg^(0))from flue gas.The modified RM underwent comprehensive characterization,including analysis of its textural qualities,crystal structure,chemical composition,and thermal properties.The results indicate that the halide impregnation substantially impacts the surface area and pore size of the RM.Hg^(0) removal performance was evaluated on a fixed-bed reactor in simulated flue gas(consisting of N_(2),O_(2),CO_(2),NO and SO_(2),etc.)on a modified RM.At an optimal adsorption temperature of 160℃,NaI-modified sorbent(RMI5)offers a removal efficiency of 98%in a mixture of gas,including O_(2),NO and HCl.Furthermore,pseudo-second-order model fitting results demonstrate the chemisorption mechanism for the adsorption of Hg^(0) in kinetic investigations. 展开更多
关键词 mercury removal red mud sodium halides IMPREGNATION flue gas
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Novel Methodologies for Preventing Crack Propagation in Steel Gas Pipelines Considering the Temperature Effect
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作者 Nurlan Zhangabay Ulzhan Ibraimova +4 位作者 Marco Bonopera Ulanbator Suleimenov Konstantin Avramov Maryna Chernobryvko Aigerim Yessengali 《Structural Durability & Health Monitoring》 EI 2025年第1期1-23,共23页
Using the software ANSYS-19.2/Explicit Dynamics,this study performedfinite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crac... Using the software ANSYS-19.2/Explicit Dynamics,this study performedfinite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crack,strengthened by steel wire wrapping.The effects of the thread tensile force of the steel winding in the form of single rings at the crack edges and the wires with different winding diameters and pitches were also studied.The results showed that the strengthening was preferably executed at a minimum value of the thread tensile force,which was 6.4%more effective than that at its maximum value.The analysis of the influence of the winding dia-meters showed that the equivalent stresses increased by 32%from the beginning of the crack growth until the wire broke.The increment in winding diameter decelerated the disclosure of the edge crack and reduced its length by 8.2%.The analysis of the influence of the winding pitch showed that decreasing the distance between the winding turns also led to a 33.6%reduction in the length of the straight crack and a 7.9%reduction in the maximum stres-ses on the strengthened pipeline cross-section.The analysis of the temperature effect on the pipeline material,within a range from-40℃ to+50℃,resulted in a crack length change of up to 5.8%.As the temperature dropped,the crack length decreased.Within such a temperature range,the maximum stresses were observed along the cen-tral area of the crack,which were equal to 413 MPa at+50℃ and 440 MPa at-40℃.The results also showed that the presence of the steel winding in the pipeline significantly reduced the length of crack propagation up to 8.4 times,depending on the temperature effect and design parameters of prestressing.This work integrated the existing methods for crack localization along steel gas pipelines. 展开更多
关键词 Crack propagation finite-element internal pressure PRESTRESSING steel gas pipeline temperature effect
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Mutual regulation of microglia and astrocytes after Gas6 inhibits spinal cord injury
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作者 Jiewen Chen Xiaolin Zeng +6 位作者 Le Wang Wenwu Zhang Gang Li Xing Cheng Peiqiang Su Yong Wan Xiang Li 《Neural Regeneration Research》 SCIE CAS 2025年第2期557-573,共17页
Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord injury.Microglia and astrocytes play key roles in the spinal cord injury micro-e... Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord injury.Microglia and astrocytes play key roles in the spinal cord injury micro-environment and share a close interaction.However,the mechanisms involved remain unclear.In this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming phenotypes.The expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord injury.In vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between them.We further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling pathway.This,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling pathways.In vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function recovery.Overall,Gas6 may play a role in the treatment of spinal cord injury.It can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord. 展开更多
关键词 ASTROCYTES AXL cell polarization gas6 Hippo signal inflammatory micro-environment intercellular interaction MICROGLIA single-cell sequencing spinal cord injury
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Mesenteric ischemia with intrasplenic gas:A case report
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作者 Hsiang-Yu Tsang Chee-Chien Yong Hao-Ping Wang 《World Journal of Clinical Cases》 SCIE 2025年第7期52-56,共5页
BACKGROUND Acute mesenteric ischemia is a life-threatening disease.Intrasplenic gas is an extremely rare finding in such cases.CASE SUMMARY We report a case of a 79-year-old woman with a history of end-stage renal dis... BACKGROUND Acute mesenteric ischemia is a life-threatening disease.Intrasplenic gas is an extremely rare finding in such cases.CASE SUMMARY We report a case of a 79-year-old woman with a history of end-stage renal disease on hemodialysis for approximately 20 years,type 2 diabetes mellitus,and atrial fibrillation who presented with two days of epigastric pain.A computed tomography scan of the abdomen revealed intraperitoneal free air and significant intrasplenic gas.Laparoscopy revealed diffuse intestinal gangrene,and acute superior mesenteric ischemia was diagnosed.The patient died within 24 hours owing to profound shock.CONCLUSION Intrasplenic gas is an extremely rare finding on computed tomography imaging in cases of acute mesenteric ischemia. 展开更多
关键词 Acute mesenteric ischemia SPLEEN Hepatic portal venous gas Pneumatosis cystoides intestinalis PROGNOSIS Case report
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Microstructure characteristics and corrosion behavior of metal inert gas welded dissimilar joints of 6005A modified by Sc and 5083 alloys
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作者 Guo-fu XU Liang LIU +7 位作者 Ying DENG Yu ZENG Jun-chang CAO Lei TANG Xiao-yan PENG Jia-qi DUAN Mei-chan LIANG Qing-lin PAN 《中国有色金属学报》 北大核心 2025年第1期60-76,共17页
The corrosion behavior and microstructure characteristics of metal inert gas(MIG)welded dissimilar joints of the 6005A alloy modified with Sc(designated as 6005A+Sc)and the 5083 alloy were investigated using corrosion... The corrosion behavior and microstructure characteristics of metal inert gas(MIG)welded dissimilar joints of the 6005A alloy modified with Sc(designated as 6005A+Sc)and the 5083 alloy were investigated using corrosion tests and microscopy techniques.Results show that the dissimilar joints exhibit strong stress corrosion cracking(SCC)resistance,maintaining substantial strength during slow strain rate tensile tests.Notably,the heat-affected zone(HAZ)and base metal(BM)on the 6005A+Sc side show superior performance in terms of inter-granular corrosion(IGC)and exfoliation corrosion(EXCO)compared to the corresponding zones on the 5083 side.The lower corrosion resistance of the 5083-BM and the 5083-HAZ can be attributed to the presence of numerous Al_(2)Mg_(3)phases and micro-scaled Al_(6)(Mn,Fe)intermetallics,mainly distributed along the rolling direction.Conversely,the enhanced corrosion resistance of the 6005A+Sc-BM and the 6005A+Sc-HAZ can be attributed to the discontinuously distributed grain boundary precipitates(β-Mg_(2)Si),the smaller grain size,and the reduced corrosive current density. 展开更多
关键词 metal inert gas welding dissimilar joint aluminum alloy corrosion microstructure
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Biochar as a Climate-Smart Agricultural Practice: Reducing Greenhouse Gas Emissions and Promoting Sustainable Farming
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作者 Muhammad Nazim Abdul Ghafoor +5 位作者 Abida Hussain Mehwish Tabassum Aamir Nawaz Muhammad Ahmad Murad Muhammad Muqarrab Ali 《Phyton-International Journal of Experimental Botany》 2025年第1期65-99,共35页
In recent years, the world has faced rising global temperatures, accumulative pollution, and energy crises, stimulating scientists worldwide to strive for eco-friendly and cost-effective solutions. Biochar has materia... In recent years, the world has faced rising global temperatures, accumulative pollution, and energy crises, stimulating scientists worldwide to strive for eco-friendly and cost-effective solutions. Biochar has materialized as a favorable tool for environmental remediation, indicating efficacy as an efficient sorbent substance for both inorganic and organic pollutants in environmental field. These unique properties exclude improved surface functionality, porous morphology, large specific surface area (SSA), cation exchange capacity (CEC), robust adsorption capabilities, environmental stability, and embedded micronutrients. Biochar exhibited potential characteristics for environmental oversight, greenhouse gas (GHG) emission reduction, and soil fertility improvement. This review explores the impact of fundamental factors such as retention time, pyrolysis temperature, gas flow rate, and reactor design on biochar yield and properties. Collected data revealed the various applications of biochar, ranging from waste management and construction materials to the adsorptive removal of hydrocarbon lubricants from aqueous media, contaminant immobilization, and carbon sequestration. It has played mostly a significant share in climate change mitigation and an important role in soil amendments. Biochar improves soil improvement by increasing water retention (10%–30%), carbon sequestration, soil surface functionality, and providing high surface area with chemical stability. The assessment also reports the prospects and contests associated with biochar application uses in various agriculture cropping ecosystems. Inclusive, this review highlights the multifaceted characteristics of biochar as an adjustable on top of a sustainable solution addressing greenhouse gas emission, carbon sequestration, and environmental stresses. However, further research is needed to understand its long-term impacts and optimal applications fully. 展开更多
关键词 AGRO-ECOLOGY BIOCHAR carbon storage greenhouse gas reduction sustainable agriculture
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Prediction of intrusive gas pores caused by resin burning in sand core for iron castings
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作者 Ji-wu Wang Xiao-long Wang +8 位作者 Yu-cheng Sun Yu-hang Huang Xiu-ming Chen Xiong-zhi Wu Na Li Jin-wu Kang Tao Jing Tian-you Huang Hai-liang Yu 《China Foundry》 2025年第1期23-32,共10页
In the production of castings,intrusive gas pore represents a kind of common defects which can lead to leakage in high gas-tightness requirement castings,such as cylinder blocks and cylinder heads for engines.It occur... In the production of castings,intrusive gas pore represents a kind of common defects which can lead to leakage in high gas-tightness requirement castings,such as cylinder blocks and cylinder heads for engines.It occurs due to the intrusion of gases generated during the resin burning of the sand core into castings during the casting process.Therefore,a gas generation and flow constitution model was established,in which the gas generation rate is a function of temperature and time,and the flow of gas is controlled by the gas release,conservation,and Darcy's law.The heat transfer and gas flow during casting process was numerically simulated.The dangerous point of cores is firstly identified by a virtual heat transfer method based on the similarity between heat transfer and gas flow in the sand core.The gas pores in castings are predicted by the gas pressure,the viscosity and state of the melt for these dangerous points.Three distinct sand core structures were designed and used for the production of iron castings,and the simulated gas pore results were validated by the obtained castings. 展开更多
关键词 gas pore numerical simulation iron casting sand core RESIN
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Research on the hazards of gas leakage and explosion in a full-scale residential building
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作者 Chengjun Yue Li Chen +2 位作者 Zhan Li Bin Feng Ruizhi Xu 《Defence Technology(防务技术)》 2025年第1期168-181,共14页
The gas explosion in residential building has always been a highly concerned problem.Explosions in homogeneous mixtures have been extensively studied.However,mixtures are often inhomogeneous in the practical scenarios... The gas explosion in residential building has always been a highly concerned problem.Explosions in homogeneous mixtures have been extensively studied.However,mixtures are often inhomogeneous in the practical scenarios due to the differences in the densities of methane and air.In order to investigate the effects of gas explosions in inhomogeneous mixtures,experimental studies involving gas leakage and explosion are conducted in a full-scale residential building to reproduce the process of gas explosion.By fitting the dimensionless buoyancy as a function of dimensionless height and dimensionless time,a distribution model of gas in large-scale spaces is established,and the mechanism of inhomogeneous distribution of methane is also be revealed.Furthermore,the stratified reconstruction method(SRM)is introduced for efficiently setting up inhomogeneous concentration fields in FLACS.The simulation results highlight that for the internal overpressure,the distribution of methane has no effect on the first overpressure peak(ΔP1),while it significantly influences the subsequent overpressure peak(ΔP2),and the maximum difference between the overpressure of homogeneous and inhomogeneous distribution is174.3%.Moreover,the initial concentration distribution also has a certain impact on the external overpressure. 展开更多
关键词 Methane distribution Inhomogeneous mixture Gradient layer gas explosion Explosive simulation
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Estimated Ultimate Recovery and Productivity of Deep Shale Gas Horizontal Wells
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作者 Haijie Zhang Haifeng Zhao +6 位作者 Ming Jiang Junwei Pu Yuanping Luo Weiming Chen Tongtong Luo Zhiqiang Li Xinan Yu 《Fluid Dynamics & Materials Processing》 2025年第1期221-232,共12页
Pressure control in deep shale gas horizontal wells can reduce the stress sensitivity of hydraulic fractures and improve the estimated ultimate recovery(EUR).In this study,a hydraulic fracture stress sensitivity model... Pressure control in deep shale gas horizontal wells can reduce the stress sensitivity of hydraulic fractures and improve the estimated ultimate recovery(EUR).In this study,a hydraulic fracture stress sensitivity model is proposed to characterize the effect of pressure drop rate on fracture permeability.Furthermore,a production prediction model is introduced accounting for a non-uniform hydraulic fracture conductivity distribution.The results reveal that increasing the fracture conductivity leads to a rapid daily production increase in the early stages.However,above 0.50 D·cm,a further increase in the fracture conductivity has a limited effect on shale gas production growth.The initial production is lower under pressure-controlled conditions than that under pressure-release.For extended pressure control durations,the cumulative production initially increases and then decreases.For a fracture conductivity of 0.10 D·cm,the increase in production output under controlled-pressure conditions is~35%.For representative deep shale gas wells(Southern Sichuan,China),if the pressure drop rate under controlled-pressure conditions is reduced from 0.19 to 0.04 MPa/d,the EUR increase for 5 years of pressure-controlled production is 41.0 million,with an increase percentage of~29%. 展开更多
关键词 Deep shale gas fracture stress sensitivity pressure-controlled production production prediction
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Optimization of production well patterns for natural gas hydrate reservoir: Referring to the results from production tests and numerical simulations
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作者 Lang-feng Mu Hao-tian Liu +2 位作者 Chi Zhang Yi Zhang Hai-long Lu 《China Geology》 2025年第1期39-57,共19页
Natural gas hydrate is a clean energy source with substantial resource potential.In contrast to conventional oil and gas,natural gas hydrate exists as a multi-phase system consisting of solids,liquids,and gases,which ... Natural gas hydrate is a clean energy source with substantial resource potential.In contrast to conventional oil and gas,natural gas hydrate exists as a multi-phase system consisting of solids,liquids,and gases,which presents unique challenges and complicates the mechanisms of seepage and exploitation.Both domestic and international natural gas hydrate production tests typically employ a single-well production model.Although this approach has seen some success,it continues to be hindered by low production rates and short production cycles.Therefore,there is an urgent need to explore a new well network to significantly increase the production of a single well.This paper provides a comprehensive review of the latest advancements in natural gas hydrate research,including both laboratory studies and field tests.It further examines the gas production processes and development outcomes for single wells,dual wells,multi-branch wells,and multi-well systems under conditions of depressurization,thermal injection,and CO_(2) replacement.On this basis,well types and well networks suitable for commercial exploitation of natural gas hydrate were explored,and the technical direction of natural gas hydrate development was proposed.The study shows that fully exploiting the flexibility of complex structural wells and designing a well network compatible with the reservoir is the key to improving production from a single well.Moreover,multi-well joint exploitation is identified as an effective strategy for achieving large-scale,efficient development of natural gas hydrate. 展开更多
关键词 gas Hydrate Production DEPRESSURIZATION Heat Injection REPLACEMENT Multi-Branch Well Well patterns Hydrate exploration engineering
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Direct ink writing of nickel oxide-based thin films for room temperature gas detection
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作者 Neha Thakur Hari Murthy +3 位作者 Sudha Arumugam Neethu Thomas Aarju Mathew Koshy Parasuraman Swaminathan 《Journal of Semiconductors》 2025年第1期245-258,共14页
The rapid industrial growth and increasing population have led to significant pollution and deterioration of the natural atmospheric environment.Major atmospheric pollutants include NO_(2)and CO_(2).Hence,it is impera... The rapid industrial growth and increasing population have led to significant pollution and deterioration of the natural atmospheric environment.Major atmospheric pollutants include NO_(2)and CO_(2).Hence,it is imperative to develop NO_(2)and CO_(2)sensors for ambient conditions,that can be used in indoor air quality monitoring,breath analysis,food spoilage detection,etc.In the present study,two thin film nanocomposite(nickel oxide-graphene and nickel oxide-silver nanowires)gas sensors are fabricated using direct ink writing.The nano-composites are investigated for their structural,optical,and electrical properties.Later the nano-composite is deposited on the interdigitated electrode(IDE)pattern to form NO_(2)and CO_(2)sensors.The deposited films are then exposed to NO_(2)and CO_(2)gases separately and their response and recovery times are determined using a custom-built gas sensing setup.Nickel oxide-graphene provides a good response time and recovery time of 10 and 9 s,respectively for NO_(2),due to the higher electron affinity of graphene towards NO_(2).Nickel oxide-silver nanowire nano-composite is suited for CO_(2)gas because silver is an excellent electrocatalyst for CO_(2)by giving response and recovery times of 11 s each.This is the first report showcasing NiO nano-composites for NO_(2)and CO_(2)sensing at room temperature. 展开更多
关键词 nickel oxide GRAPHENE silver nanowires NO_(2) CO_(2) gas sensor
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Steam Methane Reforming(SMR)Combined with Ship Based Carbon Capture(SBCC)for an Efficient Blue Hydrogen Production on Board Liquefied Natural Gas(LNG)Carriers
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作者 Ikram Belmehdi Boumedienne Beladjine +2 位作者 Mohamed Djermouni Amina Sabeur Mohammed El Ganaoui 《Fluid Dynamics & Materials Processing》 2025年第1期71-85,共15页
The objective of this study is to propose an optimal plant design for blue hydrogen production aboard a liquefiednatural gas(LNG)carrier.This investigation focuses on integrating two distinct processes—steam methaner... The objective of this study is to propose an optimal plant design for blue hydrogen production aboard a liquefiednatural gas(LNG)carrier.This investigation focuses on integrating two distinct processes—steam methanereforming(SMR)and ship-based carbon capture(SBCC).The first refers to the common practice used to obtainhydrogen from methane(often derived from natural gas),where steam reacts with methane to produce hydrogenand carbon dioxide(CO_(2)).The second refers to capturing the CO_(2) generated during the SMR process on boardships.By capturing and storing the carbon emissions,the process significantly reduces its environmental impact,making the hydrogen production“blue,”as opposed to“grey”(which involves CO_(2) emissions without capture).For the SMR process,the analysis reveals that increasing the reformer temperature enhances both the processperformance and CO_(2) emissions.Conversely,a higher steam-to-carbon(s/c)ratio reduces hydrogen yield,therebydecreasing thermal efficiency.The study also shows that preheating the air and boil-off gas(BOG)before theyenter the combustion chamber boosts overall efficiency and curtails CO_(2) emissions.In the SBCC process,puremonoethanolamine(MEA)is employed to capture the CO_(2) generated by the exhaust gases from the SMR process.The results indicate that with a 90%CO_(2) capture rate,the associated heat consumption amounts to 4.6 MJ perkilogram of CO_(2) captured.This combined approach offers a viable pathway to produce blue hydrogen on LNGcarriers while significantly reducing the carbon footprint. 展开更多
关键词 Carbon dioxide(CO_(2))emissions blue hydrogen boil-off gas(BOG) steam methane reforming(SMR) ship-based carbon capture(SBCC)
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APPLICATION OF FUZZY OPTIMIZATION MODEL IN ECOLOGICAL SECURITY PRE-WARNING 被引量:13
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作者 WUKai-ya HUShu-heng SUNShi-qun 《Chinese Geographical Science》 SCIE CSCD 2005年第1期29-33,共5页
Ecological security is a vital problem that people all over the world today have to face and solve, and the situation of ecological security is getting more and more severe and has begun to impede heavily the sustaina... Ecological security is a vital problem that people all over the world today have to face and solve, and the situation of ecological security is getting more and more severe and has begun to impede heavily the sustainable development of social economy. Ecological environment pre-warning has become a hotspot for the modern environment science. This paper introduces the theories of ecological security pre-warning and tries to constitute a pre-warning model of ecological security. In terms of pressure-state-response model, the pre-warning guide line of ecological security is constructed while the pre-warning degree judging model of ecological security is established based on fuzzy optimization. As a case, the model is used to assess the present condition pre-warning of the ecological security of Anhui Province. The result is in correspondence with the real condition: the ecological security situations of 8 cities are dangerous and 9 cities are secure. The result shows that this model is scientific and effective for regional ecological security pre-warning. 展开更多
关键词 ecological security pre-warning fuzzy optimization pre-warning model Anhui Province
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Non-destructive testing and pre-warning analysis on the quality of bolt support in deep roadways of mining districts 被引量:13
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作者 Zhang Houquan Miao Xiexing +2 位作者 Zhang Guimin Wu Yu Chen Yanlong 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第6期989-998,共10页
The bolt support quality of coal roadways is one of the important factors for the efficiency and security of coal production. By means of a self-developed technique and equipment of random non-destructive testing, non... The bolt support quality of coal roadways is one of the important factors for the efficiency and security of coal production. By means of a self-developed technique and equipment of random non-destructive testing, non-destructive detection and pre-warning analysis on the quality of bolt support in deep roadways of mining districts were performed in a number of mining areas. The measured data were obtained in the detection instances of abnormal in-situ stress and support invalidation etc. The corresponding relation between axial bolt load variation and roadway surrounding rock deformation and stability was summarized in different mining service stages. Pre-warning technology of roadway surrounding rock stability is proposed based on the detection of axial bolt load. Meanwhile, pre-warning indicators of axial bolt load in different mining service stages are offered and some successful pre-warning cases are also illustrated.The research results show that the change rules of axial bolt load in different mining service stages are quite similar in different mining areas. The change of axial bolt load is in accord with the adjustment of surrounding rock stress, which can consequently reflect the deformation and stability state of roadway surrounding rock. Through the detection of axial bolt load in different sections of roadways, the status of real-time bolt support quality can be reflected; meanwhile, the rationality of bolt support design can be evaluated which provides reference for bolting parameters optimization. 展开更多
关键词 Deep roadways BOLT support QUALITY RANDOM NONDESTRUCTIVE testing SURROUNDING ROCK stability Prediction and pre-warning
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High-rise building fire pre-warning model based on the support vector regression 被引量:1
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作者 张立宁 张奇 安晶 《Journal of Beijing Institute of Technology》 EI CAS 2015年第3期285-290,共6页
Aiming at reducing the deficiency of the traditional fire pre-warning algorithms and the intelligent fire pre-warning algorithms such as artificial neural network,and then to improve the accuracy of fire prewarning fo... Aiming at reducing the deficiency of the traditional fire pre-warning algorithms and the intelligent fire pre-warning algorithms such as artificial neural network,and then to improve the accuracy of fire prewarning for high-rise buildings,a composite fire pre-warning controller is designed according to the characteristic( nonlinear,less historical data,many influence factors),also a high-rise building fire pre-warning model is set up based on the support vector regression( SV R). Then the wood fire standard history data is applied to make empirical analysis. The research results can provide a reliable decision support framework for high-rise building fire pre-warning. 展开更多
关键词 high-rise buildings fire composite fire pre-warning systemdesign the support vector regression pre-warning model
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Geochemistry and origins of hydrogen-containing natural gases in deep Songliao Basin,China:Insights from continental scientific drilling 被引量:4
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作者 Shuang-Biao Han Chao-Han Xiang +3 位作者 Xin Du Lin-Feng Xie Jie Huang Cheng-Shan Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期741-751,共11页
The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantl... The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantly,but the origin analysis of different gas types has previously been weak.Based on the geochemical parameters of gas samples from different depths and the analysis of geological settings,this research covers the diverse origins of natural gas in different strata.The gas components are mainly methane with a small amount of C_(2+),and non-hydrocarbon gases,including nitrogen(N_(2)),hydrogen(H_(2)),carbon dioxide(CO_(2)),and helium(He).At greater depth,the carbon isotope of methane becomes heavier,and the hydrogen isotope points to a lacustrine sedimentary environment.With increasing depth,the origins of N_(2)and CO_(2)change gradually from a mixture of organic and inorganic to inorganic.The origins of hydrogen gas are complex and include organic sources,water radiolysis,water-rock(Fe^(2+)-containing minerals)reactions,and mantle-derived.The shales of Denglouku and Shahezi Formations,as source rocks,provide the premise for generation and occurrence of organic gas.Furthermore,the deep faults and fluid activities in Basement Formation control the generation and migration of mantle-derived gas.The discovery of a high content of H_(2)in study area not only reveals the organic and inorganic association of natural-gas generation,but also provides a scientific basis for the exploration of deep hydrogen-rich gas. 展开更多
关键词 gas compositions Stable isotopes gas origins Hydrogen gas Songliao Basin
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