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基于Zigbee的煤矿安全生产监控系统设计与研究

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煤矿现代化 2025年第1期34卷 144-147页

作者：贺婷晋能控股煤业集团煤峪口矿山西大同037000

针对目前有线式煤矿安全监控系统布线繁琐、灵活性差、安装及维护成本高等问题,将无线通信及物联网技术应用至煤矿安全生产监控中,提出了一种基于Zigbee无线传感器网络的煤矿安全监控系统设计方案,对多参数融合检测无线传感器节点及基... 详细信息

针对目前有线式煤矿安全监控系统布线繁琐、灵活性差、安装及维护成本高等问题,将无线通信及物联网技术应用至煤矿安全生产监控中,提出了一种基于Zigbee无线传感器网络的煤矿安全监控系统设计方案,对多参数融合检测无线传感器节点及基站传感器节点进行设计,利用无线传感网络自组织、结构灵活等特点弥补目前有线系统缺陷,实现煤矿井下环境参数及人员信息的采集、传输与监控,有效提高煤矿安全生产监控水平。

关键词：煤矿安全监控 Zigbee 无线传感器网络

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贸易政策不确定性能否提升企业社会责任?

国际商务研究 2025年第1期46卷 34-45页

作者：梁俊伟贺铭楷广东外语外贸大学广东广州510003 中电建海上风电工程有限公司海南海口570203

随着中国经济增长,进出口规模持续扩大,中国面临的贸易政策不确定性也达到了前所未有的程度。研究发现,贸易政策不确定性显著抑制了企业的ESG表现,在经过替代被解释变量以及工具变量法等一系列稳健性检验后,该结论依然成立。进一步研究... 详细信息

随着中国经济增长,进出口规模持续扩大,中国面临的贸易政策不确定性也达到了前所未有的程度。研究发现,贸易政策不确定性显著抑制了企业的ESG表现,在经过替代被解释变量以及工具变量法等一系列稳健性检验后,该结论依然成立。进一步研究发现,非国有企业、规模较小企业和所处地区市场化程度高的企业受到的抑制作用更加明显;贸易政策不确定性对非污染企业ESG表现存在抑制作用,但对重污染企业的抑制作用并不显著。贸易政策不确定性会增加企业面临的融资约束,降低企业的效率投资,进而抑制企业的ESG表现。

关键词：贸易政策不确定性 ESG 融资约束

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插芯结构对旋流冷却流动换热特性的影响

西安交通大学学报 2025年第1期59卷 105-115页

作者：何伟肖俊峰高松李园园于飞龙伍赫西安热工研究院有限公司西安710054

针对用于透平叶片前缘的旋流冷却结构,为了改善其冷气发展空间、提高综合冷却性能,提出了一种布置在冷却腔内的插芯结构。基于简化旋流冷却结构,采用数值模拟方法研究了插芯结构对旋流冷却靶面换热系数、综合冷却性能、流量分配、流动... 详细信息

针对用于透平叶片前缘的旋流冷却结构,为了改善其冷气发展空间、提高综合冷却性能,提出了一种布置在冷却腔内的插芯结构。基于简化旋流冷却结构,采用数值模拟方法研究了插芯结构对旋流冷却靶面换热系数、综合冷却性能、流量分配、流动结构等的改善效果和作用机理。结果表明:增设插芯结构后,在射流雷诺数5 000~20 000范围内,旋流冷却结构的靶面面积平均努塞尔数增加了5.9%~8.3%,综合冷效因子增加了5.2%~6.6%,吸力侧努塞尔数提高了14.8%~16.6%,相邻喷嘴间流量的最大差从18%削减到5%。插芯结构削减了上游射流在旋流腔轴心处的发展空间,抑制了旋流回流和旋流涡核的形成,降低了上游冷气对新鲜射流的干扰,强化了旋流对壁面边界层的削弱效果,从而有效增加了旋流结构的一致性并提高了靶面换热系数的强度和均匀性。

关键词：旋流冷却透平叶片内部冷却努塞尔数射流雷诺数

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miRNA-21-5p is an important contributor to the promotion of injured peripheral nerve regeneration using hypoxia-pretreated bone marrow-derived neural crest cells

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Neural Regeneration Research 2025年第1期20卷 277-290页

作者： Meng Cong Jing-Jing Hu Yan Yu Xiao-Li Li Xiao-Ting Sun Li-Ting Wang Xia Wu Ling-Jie Zhu Xiao-Jia Yang Qian-Ru he Fei Ding Hai-Yan Shi School of Medicine Nantong UniversityNantongJiangsu ProvinceChina Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education and Coinnovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Physiology Jiangsu Health Vocational CollegeNanjingJiangsu ProvinceChina Department of Pathology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina

Our previous study found that rat bone marrow–derived neural crest cells(acting as Schwann cell progenitors)have the potential to promote long-distance nerve ***-based therapy can enhance peripheral nerve repair and regeneration through paracrine bioactive factors and intercellular ***,the complex contributions of various types of soluble cytokines and extracellular vesicle cargos to the secretome remain *** investigate the role of the secretome and extracellular vesicles in repairing damaged peripheral nerves,we collected conditioned culture medium from hypoxia-pretreated neural crest cells,and found that it significantly promoted the repair of sensory neurons damaged by oxygen-glucose *** mRNA expression of trophic factors was highly expressed in hypoxia-pretreated neural crest *** performed RNA sequencing and bioinformatics analysis and found that miR-21-5p was enriched in hypoxia-pretreated extracellular vesicles of neural crest ***,to further clarify the role of hypoxia-pretreated neural crest cell extracellular vesicles rich in miR-21-5p in axonal growth and regeneration of sensory neurons,we used a microfluidic axonal dissociation model of sensory neurons in vitro,and found that hypoxia-pretreated neural crest cell extracellular vesicles promoted axonal growth and regeneration of sensory neurons,which was greatly dependent on loaded ***,we constructed a miR-21-5p-loaded neural conduit to repair the sciatic nerve defect in rats and found that the motor and sensory functions of injured rat hind limb,as well as muscle tissue morphology of the hind limbs,were obviously *** findings suggest that hypoxia-pretreated neural crest extracellular vesicles are natural nanoparticles rich in ***-21-5p is one of the main contributors to promoting nerve regeneration by the neural crest cell *** helps to explain the mechanism of action of the secretome and e

关键词： axotomy cell-free therapy conditioned medium extracellular vesicles hypoxic preconditioning microRNA oxygen-glucose deprivation peripheral nerve injury Schwann cell precursors

Effect of Progressive Substitution of Cement and Lime by Powdered Shells Used as a Curing Agent for Dredged Soil in a Port Area

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期 88-102页

作者：孙阳 WANG Faxin SU Yaying LI Yiwei he Feng College of Harbour Coastal and Offshore Engineering Hohai University Huai'an Research Institute Hohai University Jiangsu Fangyang Industrial Investment Corp. Ltd.

This study aimed to address the challenges of solid waste utilization,cost reduction,and carbon reduction in the treatment of deep-dredged soil at Xuwei Port in Lianyungang city of *** research in this area was ***,a curing agent made from powdered shells was used to solidify the dredged soil in *** employed laboratory orthogonal tests to investigate the physical and mechanical properties of the powdered shell-based curing *** was collected by conducting experiments to assess the role of powdered shells in the curing process and to determine the optimal ratios of powdered shells to solidified soil for different *** development of strength in solidified soil was studied in both seawater and pure water *** study revealed that the strength of the solidified soil was influenced by the substitution rate of powdered shells and their interaction with *** cement content had a positive effect on *** high-strength solidified soil,the recommended ratio of wet soil:cement:lime:powdered shells were 100:16:4:4,while for low-strength solidified soil,the recommended ratio was 100:5.4:2.4:***,under appropriate conditions,improved short-term strength by promoting the formation of expansive ettringite minerals that contributed to cementation and *** findings suggest that the combination of cement and powdered shells is synergistic,positively affecting the strength of solidified *** recommended ratios provide practical guidance for achieving desired strength levels while considering factors such as cost and carbon *** role of seawater in enhancing short-term strength through crystal formation is noteworthy and can be advantageous for certain *** conclusion,this research demonstrates the potential of using a powdered shell-based curing agent for solidifying dredged soil in an environmentally friendly and cost-effective *** recommended ratios for different str

关键词：

A NEW CYCLOPEPTIDE FROM VACCARIA SEGETALIS

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Chinese Chemical Letters 1995年第8期6卷 681-682页

作者： Zhang, RP Zou, C Chai, yk Zhou, J Acad Sinica Kunming Inst Bot Lab Phytochem Kunming 650204 Peoples R China

A new cyclopeptide designated as vaccarin A were isolated from the seeds of Vaccaria segetalis, Its structure was obtained by spectral evidence.

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Efficient and Stable Photoassisted Lithium-Ion Battery Enabled by Photocathode with Synergistically Boosted Carriers Dynamics

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NANO-MICRO LETTERS 2025年第1期17卷 1-15页

作者： Ma, Zelin Wang, Shiyao Ma, Zhuangzhuang Li, Juan Zhao, Luomeng Li, Zhihuan Wang, Shiyuan Shuang, Yazhou Wang, Jiulong Wang, Fang Xia, Weiwei Jian, Jie he, Yibo Wang, Junjie Guo, Pengfei Wang, Hongqiang Northwestern Polytech Univ Ctr Nano Energy Mat State Key Lab Solidificat Proc Sch Mat Sci & Engn Xian 710072 Peoples R China NPU Shaanxi Joint Lab Graphene Xian 710072 Peoples R China Northwestern Polytech Univ Sch Mat Sci State Key Lab Solidificat Proc Xian 710072 Peoples R China Northwestern Polytech Univ Engn Dept Xian 710072 Peoples R China Northwestern Polytech Univ Ctr Adv Lubricat & Seal Mat Sch Mat Sci & Engn State Key Lab Solidificat Proc Xian 710072 Peoples R China Northwestern Polytech Univ Shenzhen Res & Dev Inst Shenzhen 518063 Peoples R China Shaanxi Normal Univ Key Lab Appl Surface & Colloid Chem Shaanxi Engn Lab Adv Energy Technol Shaanxi Key Lab Adv Energy DevicesSch Mat Sci & E Xian 710119 Peoples R China

Efficient and stable photocathodes with versatility are of significance in photoassisted lithium-ion batteries (PLIBs), while there is always a request on fast carrier transport in electrochemical active photocathodes. Present work proposes a general approach of creating bulk heterojunction to boost the carrier mobility of photocathodes by simply laser assisted embedding of plasmonic nanocrystals. When employed in PLIBs, it was found effective for synchronously enhanced photocharge separation and transport in light charging process. Additionally, experimental photon spectroscopy, finite difference time domain method simulation and theoretical analyses demonstrate that the improved carrier dynamics are driven by the plasmonic-induced hot electron injection from metal to TiO2, as well as the enhanced conductivity in TiO2 matrix due to the formation of oxygen vacancies after Schottky contact. Benefiting from these merits, several benchmark values in performance of TiO2-based photocathode applied in PLIBs are set, including the capacity of 276 mAh g(-1 ) at 0.2 A g(-1 )under illumination, photoconversion efficiency of 1.276% at 3 A g(-1 ), less capacity and Columbic efficiency loss even through 200 cycles. These results exemplify the potential of the bulk heterojunction strategy in developing highly efficient and stable photoassisted energy storage systems.

关键词： Photoassisted lithium-ion batteries Bulk heterojunction Carrier dynamics TiO2 nanofiber Plasmonic metal nanocrystals

Prediction of esophageal and gastric histology by macroscopic diagnosis during upper endoscopy in pediatric celiac disease

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World Journal of Gastroenterology 2017年第4期23卷 646-652页

作者： Erin D Boschee Jason yk Yap Justine M Turner Department of Pediatrics University of Alberta Edmonton Clinic health Academy University of Alberta Hospital Division of Pediatric Gastroenterology Department of PediatricsUniversity of Alberta

AIMTo determine the sensitivity of macroscopic appearance for predicting histological diagnosis at sites other than duodenum in pediatric celiac disease (CD).METHODSEndoscopic and histologic findings in pediatric patients undergoing upper endoscopy for first-time diagnosis of CD at Stollery Children’s Hospital from 2010-2012 were retrospectively *** charts from 140 patients were reviewed. Esophageal and gastric biopsies were taken in 54.3% and 77.9% of patients, respectively. Endoscopic appearance was normal in the esophagus and stomach in 75% and 86.2%. Endoscopic esophageal diagnoses were eosinophilic esophagitis (EE) (11.8%), esophagitis (7.9%), glycogenic acanthosis (1.3%) and non-specific abnormalities (3.9%). Endoscopic gastric diagnoses were gastritis (8.3%), pancreatic rest (0.9%), and non-specific abnormalities (4.6%). Histology was normal in 76.3% of esophageal and 87.2% of gastric specimens. Abnormal esophageal histology was EE (10.5%), esophagitis (10.5%), glycogenic acanthosis (1.3%) and non-specific (1.3%). Gastritis was reported in 12.8% of specimens. Sensitivity and specificity of normal endoscopy for predicting normal esophageal histology was 86.2% and 61.1%, and for normal gastric histology was 87.4% and 21.4%.CONCLUSIONIn the absence of macroscopic abnormalities, routine esophageal and gastric biopsy during endoscopy for pediatric CD does not identify major pathologies. These findings have cost and time saving implications for clinical practice.

关键词： Endoscopy Histology Esophagus Gastric biopsy Celiac disease

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动压巷道围岩变形机理及其控制技术研究

煤矿现代化 2025年第1期34卷 58-65页

作者：贺淼鑫晋能控股装备制造集团有限公司寺河煤矿二号井山西晋城048019

针对寺河煤矿二号井动压巷道在工作面回采过程中存在的围岩变形严重及工作面支架阻力过大等问题,采用现场监测与数值模拟相结合的手段,对动压巷道围岩变形机理及其控制技术进行了系统研究。结果表明,巷道在经受掘进支护及工作面的开采... 详细信息

针对寺河煤矿二号井动压巷道在工作面回采过程中存在的围岩变形严重及工作面支架阻力过大等问题,采用现场监测与数值模拟相结合的手段,对动压巷道围岩变形机理及其控制技术进行了系统研究。结果表明,巷道在经受掘进支护及工作面的开采动压影响后,围岩应力水平升高,且两侧应力不平衡,帮部不对称变形严重,巷道围岩变形主要分为单侧采用影响与两侧采动影响2个阶段,巷道变形主要是因为采区大巷两侧工作面采动产生的应力扰动作用,导致巷道承载性能持续恶化,围岩发生反复变形破坏。据此,研究提出采用预裂切顶卸压技术对动压巷道变形实施有效控制,确定合理的切顶卸压高度与角度分别为16.5 m与60°。通过现场实践,对动压巷道实施切顶卸压后,围岩顶底板及两帮移近量较卸压前得到了有效控制,工作面支架阻力显著降低,保证了工作面动压巷道围岩的稳定。

关键词：动压巷道围岩变形切顶卸压数值模拟