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金属地下矿山顶帮板管理思路

世界有色金属 2024年第10期 211-213页

作者：王杰王卫生陈杰铜陵有色金属集团铜冠矿山建设股份有限公司安徽铜陵244000

金属地下矿山安全管理重点之一是顶帮板管理。相关资料显示,在矿山整体安全效果显著提升时,冒顶片帮事故仍然占事故总数的较大比重。本文从顶帮板风险分级管控切入,结合隐患排查治理的实践要求,探讨科学有效地建立顶帮板安全管理双重预... 详细信息

金属地下矿山安全管理重点之一是顶帮板管理。相关资料显示,在矿山整体安全效果显著提升时,冒顶片帮事故仍然占事故总数的较大比重。本文从顶帮板风险分级管控切入,结合隐患排查治理的实践要求,探讨科学有效地建立顶帮板安全管理双重预防机制,切实保障从业人员生命健康和财产安全,促进矿山企业安全高质量发展。

关键词：金属矿山顶帮板管理分级管控隐患排查安全职责技术交底应急处置

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Research and application of real-time monitoring and early warning thresholds for multi-temporal agricultural products information

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Journal of Integrative Agriculture 2020年第10期19卷 2582-2596页

作者： XU Shi-wei wang Yu wang sheng-wei LI Jian-zheng Key Laboratory of Agricultural Information Service Technology of the Ministry of Agriculture and Rural Affairs Bejing 100081P.R.China Research Center of Agricultural Monitoring and Early Warning Engineering Technologies Beijing 100081P.R.China Key Open Laboratory of Itelligent Agricultural Early Warning Technologies and Systems Chinese Academy of Agricultural SciencesBejjing 100081P.R.China Agriculture Information Institute Chinese Academy of Agricultural SciencesBeiing 100081P.R.China

Monitoring and early warning is an important means to effectively prevent risks in agricultural production,consumption and *** particular,with the change of modes of national administration against the background of big data,improving the capacity to monitor agricultural products is of great significance for macroeconomic *** product information early warning thresholds are the core of agricultural product monitoring and early *** to appropriately determine the early warning thresholds of multi-temporal agricultural product information is a key question to realize real-time and dynamic monitoring and early *** on the theory of abnormal fluctuation of agricultural product information and the research of substantive impact on the society,this paper comprehensively discussed the methods to determine the thresholds of agricultural product information fluctuation in different time *** on the data of the National Bureau of Statistics of China(NBSC)and survey data,this paper used a variety of statistical methods to determine the early warning thresholds of the production,consumption and prices of agricultural *** with Delphi expert judgment correction method,it finally determined the early warning thresholds of agricultural product information in multiple time,and carried out early warning analysis on the fluctuation of agricultural product monitoring information in *** results show that:(1)the daily,weekly and monthly monitoring and early warning thresholds of agricultural products play an important early warning role in monitoring abnormal fluctuations with agricultural products;(2)the multitemporal monitoring and early warning thresholds of agricultural product information identified by the research institute can provide effective early warning on current abnormal fluctuation of agricultural product information,provide a benchmarking standard for China's agricultural production,consumption a

关键词： agricultural product information monitoring and early warning threshold multi-temporal real-time dynamics

The Removal and Remediation of Phenanthrene and Pyrene in Soil by Mixed Cropping of Alfalfa and Rape

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Agricultural Sciences in China 2008年第11期7卷 1355-1364页

作者： PAN sheng-wang wei Shi-qiang YUAN Xin CAO sheng-xian Key Laboratory of Agricultural Resources and Environment in Chongqing College of Resources and Environment Southwest University Chongqing 400716 P.R.China

The mechanisms and efficiencies of the removal and remediation of polycyclic aromatic hydrocarbons （PAHs） in soils by different planting patterns with rape （Brassica campestris） and alfalfa （Medicago sativa） were studied by pot experiments in a greenhouse. Results showed that the remediation efficiencies under mixed cropping of alfalfa and rape significantly exceeded those under single cropping when the initial concentrations of phenanthrene and pyrene were at 20.05-322.06 mg kg^-1 and 20.24-321.42 mg kg^-1, respectively. After 70 days plantation of crops, the contents of extractable PAHs in soils under mixed cropping were much lower than those under single cropping. About 65.17-83.52% of phenanthrene and 60.09%- 75.34% ofpyrene was removed from the soils under mixed cropping, respectively, which were averagely 43.26 and 40.38% for phenanthrene, and 11.03 and 16.29% for pyren higher than those under single cropping. Alfalfa or rape did absorb and accumulate PAHs from the soils apparently; the PAHs concentrations in plants monotonically increased with the increase of initial PAHs concentrations in soil; the accumulations of PAHs in plants showed following sequence as roots 〉 above parts, phenanthrene 〉 pyrene and single cropping 〉 mixed cropping at same contamination level. Despite the presence of vegetation significantly enhanced the remediation of PAHs in soils, contributions of abiotic loss, plant uptake, accumulation and microbial degradation was much lower than those of plant-microbial interactions in the process of phytoremediation. Thus plant-microbial interactions are the main mechanisms for the remediation enhancement of soil PAHs pollution under mixed cropping models. Results suggested a feasibility of the establishment of multi-species phytoremediation for the improvement of remediation efficiencies of PAHs, which may decrease accumulations of PAHs in crops and thus reduce their risks.

关键词： phytoremediation polycyclic aromatic hydrocarbons mixed cropping models plant-microbial interactions soil

腰椎管狭窄症内镜减压影像与临床资料的相关性

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中国矫形外科杂志 2024年第3期32卷 220-225页

作者：王生伟谈应东陈丽娟毛义义运彩虹甘肃省酒泉市人民医院放射科甘肃酒泉735000 甘肃省酒泉市人民医院骨科甘肃酒泉735000

[目的]探讨腰椎管狭窄症(lumbar spinal stenosis,LSS)内镜减压影像与临床资料的相关性。[方法]2020年1月—2022年8月本院对76例LSS患者行经皮经椎间孔内镜减压术。末次随访时按改良Macnab评价临床疗效将患者分组,比较患者临床与影像资... 详细信息

[目的]探讨腰椎管狭窄症(lumbar spinal stenosis,LSS)内镜减压影像与临床资料的相关性。[方法]2020年1月—2022年8月本院对76例LSS患者行经皮经椎间孔内镜减压术。末次随访时按改良Macnab评价临床疗效将患者分组,比较患者临床与影像资料,分析末次随访影像参数与VAS评分、ODI指数的相关性。[结果]按Macnab标准,末次随访时临床结果评定为优36例,良32例,可8例,此三组患者的VAS评分[(1.3±0.2)vs(1.7±0.4)vs(2.6±0.8),P<0.001]、ODI指数[(20.9±4.3)%vs(25.5±5.3)%vs(32.4±3.4)%,P<0.001]、中央椎管横断面积[(169.3±18.3)mm^(2)vs(164.5±15.8)mm^(2)vs(156.4±13.4)mm^(2),P<0.001]、侧隐窝前后径[(5.3±0.7)mm vs(4.9±0.6)mm vs(4.2±0.4)mm,P<0.001]、椎间孔矢状面积[(90.2±9.0)mm^(2)vs(86.4±8.1)mm^(2)vs(80.5±6.8)mm^(2),P<0.001]、硬膜囊横断面积[(138.5±10.3)mm^(2)vs(134.4±9.2)mm^(2)vs(126.3±8.6)mm^(2),P<0.001]和硬膜囊最大矢状径[(21.7±4.0)mm vs(19.6±3.3)mm vs(17.9±2.8)mm,P<0.001]的差异均有统计学意义。相关分析表明:VAS评分与中央椎管横断面积(r=-0.429,P<0.001),侧隐窝前后径(r=-0.346,P<0.001),椎间孔矢状面积(r=-0.354,P<0.001),硬膜囊横断面积(r=-0.216,P=0.023)和硬膜囊最大矢状径(r=-0.254,P=0.014)均呈显著负相关;ODI评分与中央椎管横断面积(r=-0.420,P<0.001)、侧隐窝前后径(r=-0.335,P<0.001)、椎间孔矢状面积(r=-0.373,P<0.001)、硬膜囊横断面积(r=-0.213,P=0.022)和硬膜囊最大矢状径(r=-0.252,P=0.013)均呈显著负相关。[结论]LSS经皮经椎间孔脊柱内镜治疗后CT、MRI影像测量参数与临床疼痛、功能障碍评分具有显著关联。

关键词：腰椎管狭窄症经皮经椎间孔脊柱内镜治疗影像学参数疗效

Observation of the Hyperfine Structure of the 2^(3)∏_(1g) State in Na2

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Chinese Physics Letters 2001年第10期18卷 1341-1343页

作者： wang wei-sheng SHANG Jian-Yuan Sun Zhen-Rong wang ZU-GENG Key Laboratory for Optical and Magnetic Resonance Spectroscopy and Department of PhysicsEast China Normal UniversityShanghai 200062 Department of Electronic Puzhou UniversityPuzhou 350002 Department of Physics and Center of Atomic and Molecular Sciences Tsinghua UniversityBeijing 100084

We report the results of the hyperfine structure (HFS) of the 2^(3)∏_(1g) state in Na_(2). The relative ultraviolet and visible fluorescence spectra of molecular sodium were measured by means of a Doppler-free two-photon spectroscopy technique. The HFS of the 23Hg(v = 78, J = 37,Ω = 1) level was first observed and its HFS constant was measured to be C = -4.92 ± 0.26 MHz. The intermediate enhancing and upper energy levels were labelled by the experimental and theoretical methods.

关键词： technique. methods. ultraviolet

Arg-gly-asp-mannose-6-phosphate inhibits activation and proliferation of hepatic stellate cells in vitro

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World Journal of Gastroenterology 2006年第8期12卷 1303-1307页

作者： Lian-sheng wang Ying-wei Chen Ding-Guo Li Han-Ming Lu Digestive Disease Laboratory Xinhua Hospital Shanghai Second Medical University Shanghai 200092 China

AIM： To investigate the effect of arg-gly-asp-mannose-6 phosphate （RGD-M6P） on the activation and proliferation of primary hepatic stellate cells in vitro. METHODS： Hepatic steUate cells （HSCs） were isolated from rats by in situ collagenase perfusion of liver and 18% Nycodenz gradient centrifugation and cultured on uncoated plastic plates for 24 h with DMEM containing 10% fetal bovine serum （FBS/DMEM） before the culture medium was substituted with 2% FBS/DMEM for another 24 h. Then, HSCs were cultured in 2% FBS/DMEM with transforming growth factor 131, M6P, RGD, or RGD- M6P, respectively. Cell morphology was observed under inverted microscope, smooth muscle α-actin （α-SMA） was detected by immunocytochemistry, type Ⅲ procollagen （PCⅢ） in supernatant was determined by radioimmunoassay, and the proliferation rate of HSCs was assessed by flow cytometry. RESULTS： RGD-M6P significantly inhibited the morphological transformation and the α-SMA and PC Ⅲ expressions of HSCs in vitro and also dramatically prevented the proliferation of HSCs in vitro. Such effects were remarkably different from those of RGD or M6R CONCLUSION： The new compound, RGD-M6P, which has a dramatic effect on primary cultured HSCs in vitro, can inhibit the transformation of HSCs in culture caused by TGFβ1, suppresses the expression of PCIII and decreases proliferation rate of HSC. RGD-M6P can be applied as a selective drug carrier targeting at HSCs, which may be a new approach to the prevention and treatment of liver fibrosis.

关键词： RGD Mannose-6-phosphate Hepatic stellate cell Liver fibrosis

A new dihydrobenzofuran lignanoside from Selaginella moellendorffii Hieron

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Chinese Chemical Letters 2008年第1期19卷 79-81页

作者： Xiao Ke Zheng Ke Ke Li Yan Zhi wang wei sheng Feng Henan College of Traditional Chinese Medicine Zhengzhou 450008 China

A new lignanoside, （7R,8S）-7,8-dihydro-7-（4-hydroxy-3,5-dimethoxyphenyl）-1＇-formyl-3＇-y-methoxyl-8-hydroxymethylbenzo- furan-4-O-β-D-glucopyranoside （moellenoside A）, was isolated from Selaginella moellendorffii Hieron. Its structure was determined by spectroscopic evidences. 2007 wei sheng Feng. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Selaginella moellendorffii Hieron Lignanoside Moellenoside A

Regression Method for Rail Fastener Tightness Based on Center-Line Projection Distance Feature and Neural Network

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 356-371页

作者： Yuanhang wang Duxin Liu sheng Guo Yifan Wu Jing Liu wei Li Hongjie wang Robotics Research Center School of MechanicalElectronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China China Construction Industrial&Energy Engineering Group Co. Ltd.Nanjing 210023China

In the railway system,fasteners have the functions of damping,maintaining the track distance,and adjusting the track ***,routine maintenance and inspection of fasteners are important to ensure the safe operation of track ***,assessment methods for fastener tightness include manual observation,acoustic wave detection,and image *** are limitations such as low accuracy and efficiency,easy interference and misjudgment,and a lack of accurate,stable,and fast detection *** at the small deformation characteristics and large elastic change of fasteners from full loosening to full tightening,this study proposes high-precision surface-structured light technology for fastener detection and fastener deformation feature extraction based on the center-line projection distance and a fastener tightness regression method based on neural ***,the method uses a 3D camera to obtain a fastener point cloud and then segments the elastic rod area based on the iterative closest point algorithm *** component analysis is used to calculate the normal vector of the segmented elastic rod surface and extract the point on the centerline of the elastic *** point is projected onto the upper surface of the bolt to calculate the projection ***,the mapping relationship between the projection distance sequence and fastener tightness is established,and the influence of each parameter on the fastener tightness prediction is ***,by setting up a fastener detection scene in the track experimental base,collecting data,and completing the algorithm verification,the results showed that the deviation between the fastener tightness regression value obtained after the algorithm processing and the actual measured value RMSE was 0.2196 mm,which significantly improved the effect compared with other tightness detection methods,and realized an effective fastener tightness regression.

关键词： Railway system Fasteners Tightness inspection Neural network regression 3D point cloud processing

Chalcogen-dependent catalytic properties of RuX2 (X = S/Se/Te) nanoparticles decorated carbon nanofibers for hydrogen evolution in acidic and alkaline media

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Nano Research 2024年第4期17卷 2528-2537页

作者： Chengkai He Yue wei Jia Xu Yujie wei Tao wang Rongfei Liu Lvlv Ji Zhun Liu sheng wang School of Materials Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Department of Physics Shaoxing UniversityShaoxing 312000China Zhejiang Kangjiesi New Material Technology Co. LTDZhuji 311800China

Transition metal dichalcogenides(TMDs),with the general formula MX_(2)(M=Mo/W/Fe/Co/Ni,etc.;X=S/Se/Te),have attracted extensive research interests for hydrogen evolution reaction(HER).Compared with numerous studies on noble-metal-free TMDs,the chalcogen-dependent HER catalytic properties of noble-metal-based TMDs are lack of sufficient research ***,a facile electrospinning-assisted synthetic strategy is proposed to synthesize ruthenium dichalcogenides(RuX_(2),X=S/Se/Te)nanoparticles decorated carbon nanofibers(CNFs).Benefiting from the identical nanofibrous morphology and exposed crystal planes of RuX_(2)(111),the catalytic activities of RuX_(2)@CNFs samples were investigated and compared in a fair and direct *** electrochemical measurements coupled with density functional theory calculations were carried out to probe their intrinsic HER catalytic activities,resulting in the catalytic activity order of RuS_(2)@CNFs>RuSe_(2)@CNFs>RuTe_(2)@CNFs in acidic media and that of RuS_(2)@CNFs>RuTe_(2)@CNFs>RuSe_(2)@CNFs in alkaline *** superior catalytic performance of RuS_(2)@CNFs mainly stems from the relative lower HER energy barriers and thereby the higher intrinsic catalytic activity of RuS_(2)(111),leading to ultralow overpotentials of 44 and 9 mV at 10 mA·cm^(-2) in acidic and alkaline media,***_(2)(111)is endowed with the more optimized Gibbs free energy of hydrogen adsorption(ΔGH*)than RuTe_(2)(111),but RuTe_(2)(111)shows enhanced catalytic property for H_(2)O dissociation and OH-desorption than RuSe_(2)(111),therefore,resulting in the altered catalytic activity sequences for RuSe_(2) and RuTe_(2) in acidic and alkaline media.

关键词： hydrogen evolution reaction transition metal dichalcogenides carbon nanofibers electrocatalysis catalytic activity