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Effect of periodic wide atmospheric pressure change on CO emission in closed goaf

International Journal of Coal Science & Technology 2023年第4期10卷 139-150页

作者： Zhuangzhuang Shao Bo Tan Ruili Hu Xiaozhen Song Yan Guo Tianze Li Shuhui Fu Chaohuan Chen Haiyan Wang School of Emergency Management and Safety Engineering China University of Mining and Technology(Beijing)Beijing 100083China Security Department University of International Business and EconomicsBeijing 100029China School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China

Atmospheric pressure fuctuation is one of the most important factors afecting the climate environment and gas emission in the fre *** obtain the infuence rule of the surface atmospheric pressure change on the gas sampling and abnormal emission in the mine closed goaf,the No.1 coal mine in Dananhu was taken as the research *** Fourier transform and Fisher harmonic analysis and other statistical methods,the infuence of the periodic variation of atmospheric pressure on the gas leakage and outfow in the closed goaf was *** results showed that there were three atmospheric pressure periods of 15.2 d,1 d and 182.2 d,and the probability was greater than 95%.The time period with the highest number of atmospheric pressure peaks was 7:00–8:00,which accounted for 20.2%of total occurrence number in a *** the time periods with the highest number of atmospheric pressure trough were 2:00,15:00 and 16:00,accounting for 27.4%.The peak-to-trough transition time was mainly concentrated around 6 h,and the diurnal variation curve of atmospheric pressure was mainly *** atmospheric pressure change rate was mostly concentrated in 10–50 Pa/*** was determined that the distance that the gas sampling pipe was pre-laid into the inner side of the closed wall should be greater than 44.4 m,and the CO concentration and atmospheric pressure in the closed goaf were both periodic and negative with atmospheric *** research results have important guiding signifcance for the monitoring,early warning and environmental protection of the goaf.

关键词： Atmospheric pressure Periodic variation Closed goaf CO emission Coal mine

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Overexpression of the PdpapERF109 gene enhances resistance of Populus davidiana×*** *** to Fusarium oxysporum infection

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Journal of Forestry research 2022年第6期33卷 1925-1937页

作者： Jian Diao Mingrui Li Ping Zhang Cheng Zong Wei Ma Ling Ma College of Forestry Northeast Forestry UniversityHarbinPeople’s Republic of China College of Wildlife and Protected Area Northeast Forestry UniversityHarbinPeople’s Republic of China College of Medicine Heilongjiang University of Chinese MedicineHarbinPeople’s Republic of China

The key transcription factor gene PdP apE RF109 was cloned from Populus davidiana×*** ***(Pdpap),and after overexpression of P dP ap ERF109 in transformants,the gene functions in the resistance response to Fusarium oxysporum *** with the wild Pdpap,after inoculation with ***,the physiological and biochemical characteristics,including relative fresh weight,peroxidase activity,and the percentage of electrolyte leakage showed that,after overexpression of the PdPapERF109 gene,the transformants grew well and displayed significant resistance to *** *** comparing the reactive oxygen species scavenging capacity of Pdpap plants after pathogen infection,the P dPapERF109-overexpressing plants had significantly better reactive oxygen species scavenging ability than the wild *** analysis of plant morphology and various physiological and biochemical parameters showed that the overexpression of the P dpapERF109 gene significantly improved the resistance of Pdpap plants to *** root ***,increasing the expression of the homologous ERF109 gene can be an effective strategy to increase disease resistance in hybrid poplars.

关键词： ERF Fusarium oxysporumtolerance Gene over-expression Genetic transformation Transcription factor

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Lensless imaging through thin scattering layers under broadband illumination

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Photonics research 2022年第11期10卷 2471-2487页

作者： WEI LI BINGJIAN WANG TENGFEI WU FEIHU XU XIAOPENG SHAO School of Optoelectronic Engineering Xidian UniversityXi’an 710071China School of Physics Xidian UniversityXi’an 710071China Laboratoire Kastler Brossel ENS–UniversitéPSLCNRSSorbonne UniversitéCollege de FranceF-75005 ParisFrance Hefei National Laboratory for Physical Sciences at Microscale and School of Physical Science University of Science and Technology of ChinaHefei 230026China

Lensless scattering imaging is a prospective approach to microscopy in which a high-resolution image of an object is reconstructed from one or more measured speckle patterns, thus providing a solution in situations where the use of imaging optics is not possible. However, current lensless scattering imaging methods are typically limited by the need for a light source with a narrowband spectrum. Here, we propose two general approaches that enable single-shot lensless scattering imaging under broadband illumination in both noninvasive [without point spread function(PSF) calibration] and invasive(with PSF calibration) modes. The first noninvasive approach is based on a numerical refinement of the broadband pattern in the cepstrum incorporated with a modified phase retrieval strategy. The latter invasive approach is correlation inspired and generalized within a computational optimization framework. Both approaches are experimentally verified using visible radiation with a full-width-at-half-maximum bandwidth as wide as 280 nm(Δλ∕λ = 44.8%) and a speckle contrast ratio as low as 0.0823. Because of its generality and ease of implementation, we expect this method to find widespread applications in ultrafast science,passive sensing, and biomedical applications.

关键词： spectrum illumination speckle

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Experimental investigation on the radiation background inside body counters

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Nuclear Science and Techniques 2022年第2期33卷 66-78页

作者： Yu Wang Yuan-Yuan Liu Bin Wu Xiang-Peng Meng Jian-Ping Cheng Ying Wang Li-Jiao Wang Yun-Shi Xiao Qin-Jian Cao Jian-Feng Zhang Fei Tuo Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Department of Nuclear Safety China Institute of Atomic EnergyBeijing 102413China Department of Health Physics China Institute for Radiation ProtectionTaiyuan 030006China National Institute for Radiological Protection Chinese Center for Disease Control and PreventionBeijing 100088China

In vivo measurement of radioactivity based on various body counters is arguably the leading measure used to determine the distribution and activity of radionuclides in human subjects,such as I-131 in the thyroid,Am-241 in the lungs,and Pb-210 in the *** the measurements,the radiation background is the key factor that determines the sensitivity of the ***,to facilitate in vivo measurements,a well-designed shielding room is required to create a low-background ***,because the compositions of the radiation background are quite complicated,the respective contributions from each source remain obscure,which places a considerable burden on seeking an optimized design of shielding rooms that strikes the optimum balance between the construction cost and background suppression *** this study,we conducted a systematic experimental investigation on the radiation background outside and inside four representative body counters with assorted designs using a variety of radiation detectors,including high-purity germanium detectors,CdZnTe detector,radon emanometer,and gamma-ray *** carefully controlling the experimental conditions and synergetic analysis of the measurement results,in conjunction with previous studies,we separated and determined the relative contributions induced by environmental radiation(4%),airborne radon and its daughters(2%),the normal radioactivity of human subjects arising from K-40(58%),cosmic rays(12%),and radioactivity in shielding materials and measuring instruments(24%).Furthermore,based on these results,we discuss practical guidelines to design a shielding room for body counters.

关键词： Body counter Radiation background Shielding room In vivo measurement

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Ca^(2+) is involved in muscarineacetylcholine-receptor-mediated acetylcholine signal transduction in guard cells of Vicia faba L.

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Chinese Science Bulletin 2004年第5期49卷 471-475页

作者： MENGFanxia MIAOLong ZHANGShuqiu LOUChenghou StateKeyLaboratoryofPlantPhysiologyandBiochemistry CollegeofiologicalSciencesChinaAgriculturalUniversityBeijing100094.China

Acetyicholine (ACh) is an important neuro-chemical transmitter in animals; it also exists in plants and plays a significant role in various kinds of physiological functions in plants. ACh has been known to induce the stomatal opening. By monitoring the changes of cytusolic Ca^2+ with fluorescent probe Fiuo-3 AM under the confocal microscopy, we found that exogenous ACh increased cytosolic Ca^2+ concentration of guard cells of Vicia faba L. Muscarlne, an agonist of muscarine acetyicholine receptor (mAChR), could do so as well. In contrast, atropine, the antagonist of mAChR abolished the ability of ACh to increase Ca^2+ in guard cells. This mechanism is similar to mAChR in animals. When EGTA was used to chelate Ca^2+ or ruthenium red to block Ca^2+ released from vacuole respectively, the results showed that the increased cytosolic Ca^2+ mainly come from intracellular Ca^2+ store. The evidence supports that Ca^2+ is involved in guard-cell response to ACh and that Ca^2+ sigual is coupled to mAChRs in ACh signal transduction in guard cells.

关键词：钙离子蝇蕈碱乙酰胆碱保卫细胞蚕豆杀螨剂

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Distinguishing ectomycorrhizal and saprophytic fungi using carbon and nitrogen isotopic compositions

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Geoscience Frontiers 2012年第3期3卷 351-356页

作者： Weiguo Hou Bin Lian Hailiang Dong Hongchen Jiang Xingliang Wu State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences Beijing 100083 China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Department of Geology and Environmental Earth Science Miami University Oxford OH 45056 USA Guizhou Academy of Sciences Guiyang 550001 China

Ectomycorrhizal fungi, a group of widespread symbiotic fungi with plant, obtain carbon source from trees and improve plant mineral nutrient uptake with their widespread hyphal network. Ectomycorrhizal fungi can be used as inoculants to improve the survival rates of plantation. Saprophytic fungi use the nutrition from the debris of plant or animals, and it is difficult to distinguish the saprophytic and ectomycorrhizal fungi by morphological and anatomic methods. In this research, the differences of stable carbon and nitrogen isotopic compositions of these fungi were analyzed. The results showed that the abundances of 13C of were higher than those of ectomycorrhizal fungi and the abundances of 15N of saprophytic fungi were lower than those of ectomycorrhizal fungi. Such differences of stable carbon and nitrogen isotopic compositions between ectomycorrhizal fungi and saprophytic fungi can be ascribed to their different nutrition sources and ecological functions. These results collectively indicate that stable carbon and nitrogen isotopic compositions are an effective proxy for distinguishing between ectomycorrhizal and saprophytic fungi.

关键词： Ectomycorrhizal fungi Saprophytic fungi Stable isotopiccompositions Ecological function

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Developing cold-resistant high-adhesive electronic substrate for WIMPs detectors at CDEX

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Chinese Physics B 2020年第4期29卷 72-76页

作者：刘圆圆程建平庞盼廖斌吴彬英敏菊张丰收陈琳吕沙沙刘言东孙天希 Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Beijing Radiation Center Beijing 100875China

Herein we report a prototypical electronic substrate specifically designed to serve the weakly interacting massive particles(WIMPs)detectors at the China Dark Matter Experiment(CDEX).Because the bulky high-purity germanium(HPGe)detectors operate under liquid-nitrogen temperatures and ultralow radiation backgrounds,the desired electronic substrates must maintain high adhesivity across different layers in such cold environment and be free from any radioactive *** conquer these challenges,for the first time,we employed polytetrafluoroethylene((C2F4)n)foil as the base substrate,in conjunction with ion implantation and deposition techniques using an independently developed device at Beijing Normal university for surface modification prior to *** remarkable peeling strengths of 0.88±0.06 N/mm for as-prepared sample and 0.75±0.05 N/mm for that after 2.5-days of soaking inside the liquid nitrogen were observed,while the regular standards commonly require 0.4 N/mm^0.6 N/mm for electronic substrates.

关键词： WIMPs detector CDEX surface modification electronic substrate

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The Significance of Wettability in Tight Oil Exploration and Development

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Acta Geologica Sinica(English Edition) 2015年第A1期89卷 172-174页

作者： XUE Haitao TIAN Shansi LU Shuangfang XIE Liujuan China university of Petroleum(Hua Dong) Unconventional oil and gas and New Energy Research Institute

With the increasing of energy demand and conventional oil and gas resources depletion, unconventional oil and gas resources are getting more and more attention, and have become a major contributor to the global oil an... 详细信息

关键词： PETROLEUM reservoirs PETROLEUM prospecting WETTING OIL fields QUANTITATIVE research

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The Green Marketing Strategies in Railway Industry Based on Recycling Economy

The Green Marketing Strategies in Railway Industry Based on ...

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工程和商业管理国际学术会议

作者： Fenling Feng School of Traffic and Transportation Engineering, central South university, Changsha, P.R.China, 410075

Making reasonable marketing strategies is the basis for the development of railway industry, and it is necessary to develop recycling economy for the sustainable development of railway industry. The thesis analyzes the problems existed in the railway marketing. Besides, it explores the relationship between recycling economy and green marketing, and suggests that recycling economy is the theory basis of green marketing, while the later one is the important method to develop recycling economy. What's more, it put up with the methods to carry on green marketing strategies. They are designing scientific railway recycling development, making and improving law, rule, policy and standards related to recycling economy in railway industry, and implementing the idea of recycling economy, carrying on green marketing and making green marketing mix. There are four powerful functions in the process of establishing green marketing system which is enterprises, consumers, the government and environmental NGOs (non-governmental organizations).

关键词： railway marketing strategies recycling economy

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