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Impact of Electricity Shortages on Productivity: Evidence from Manufacturing Industries

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Energy Engineering 2021年第4期118卷 995-1008页

作者： Xinhong Xue zhongcheng wang School of Finance Anhui University of Finance&EconomicsBengbu233030China School of International Trade and Economics Anhui University of Finance&EconomicsBengbu233030China

Electricity shortages present a significant constraint on manufacturers,who rely on electricity as an important input into production.In China,electricity supply has been growing rapidly.However,the rapid industrialization sometimes makes the power supply still unable to meet the demand.Using a survey of 1673 Chinese manufacturing firms,this paper explores how firms response to electricity shortages and its impact on productivity.We find that self-generation of electricity and investment in Research and Development(R&D)have significant positive relationships with electricity shortages.Further investigations reveal that self-generation is the most common way to deal with electricity shortages.However,it aggravates productivity loss.Though investment in Research and Development can promote productivity,it cannot offset the negative impact of electricity shortages on productivity.Analyses on subsamples show heterogeneity in the impacts of electricity shortages across firms.In particular,large firms are more inclined to invest in R&D than small and medium-sized firms are.They are also the one who suffer significant productivity loss due to self-generation of electricity.Though it is possible for medium-sized firms to reduce productivity loss through R&D,they are not likely to invest in R&D as a response to electricity shortages.This study illustrates that firms can hardly have effective solutions to electricity shortages,and policy makers should take great efforts to increase electricity supply.

关键词： Electricity shortages research and development productivity electricity efficiency

Reviews on Current Carbon Emission Reduction Technologies and Projects and their Feasibilities on Ships

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Journal of Marine Science and Application 2017年第2期16卷 129-136页

作者： Haibin wang Peilin Zhou zhongcheng wang Department of Naval Architecture Ocean and Marine Engineering University of Strathclyde Glasgow G4 0LZ UK Shanghai Maritime University Merchant Marine College Shanghai 201306 China

Concern about global climate change is growing, and many projects and researchers are committed to reducing greenhouse gases from all possible sources. International Maritime Organization (IMO) has set a target of 20% CO2 reduction from shipping by 2020 and also presented a series of carbon emission reduction methods, which are known as Energy Efficiency Design Index (EEDI) and Energy Efficiency Operation Indicator (EEOI). Reviews on carbon emission reduction from all industries indicate that, Carbon Capture and Storage (CCS) is an excellent solution to global warming. In this paper, a comprehensive literature review of EEDI and EEOI and CCS is conducted and involves reviewing current policies, introducing common technologies, and considering their feasibilities for marine activities, mainly shipping. Current projects are also presented in this paper, thereby illustrating that carbon emission reduction has been the subject of attention from all over the world. Two case ship studies indicate the economic feasibility of carbon emission reduction and provide a guide for CCS system application and practical installation on ships.

关键词： marine environment control carbon reduction technologies EEDI EEOI CCS chemical absorption

无损检测指标与木材横纹局部抗压强度和密度的相关性

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北京林业大学学报 2024年第5期46卷 136-142页

作者：王忠铖杨娜李久林北京城建集团有限责任公司北京100088 北京交通大学土木建筑工程学院北京100044

【目的】探索不同类型和数量的无损检测(NDT)指标与木材横纹局部抗压强度和密度的相关性差异,确定最优NDT指标组合,为基于无损检测手段评估木材横纹局部抗压强度和密度的研究提供参考。【方法】以某典型藏式古建筑木结构梁构件为研究对... 详细信息

【目的】探索不同类型和数量的无损检测(NDT)指标与木材横纹局部抗压强度和密度的相关性差异,确定最优NDT指标组合,为基于无损检测手段评估木材横纹局部抗压强度和密度的研究提供参考。【方法】以某典型藏式古建筑木结构梁构件为研究对象,锯解得到横纹局部抗压无疵试样。通过物理力学试验和NDT试验,获得无疵试样的密度ρ、横纹局部抗压强度f_(lc),以及顺纹应力波速v_(l)、横纹应力波速v和微钻阻力F,计算不同NDT指标或指标组合与ρ、f_(lc)的线性相关系数,进而对比讨论。【结果】(1)使用单一NDT指标预测ρ时,v_(l)效果较好,两者相关系数绝对值为0.662,补充微钻阻力均值Fm后可提高15.56%,达到0.765;使用单一NDT指标预测f_(lc)时,Fm效果较好,两者相关系数为0.526,在此基础上补充横纹应力波速均值v_(m),二者相关系数提升26.80%,达到0.667,进一步补充v_(l)后相关系数继续提升7.20%,达到0.715。(2)当两组NDT指标中的基本指标构成一致时,即便基本指标的形式存在差异,两组NDT指标与被预测参数的相关系数也近似。(3)当两个与被预测参数相关性较好的NDT指标组合时,相关系数可能进一步提高;当相关性较好的指标与较差的指标组合时,相关系数接近于前者;当相关性较差的指标与不相关指标组合时,相关系数可能大幅提升,也可能仍然较低;当两个均不显著相关的指标组合时,指标组合与被预测参数仍不具有显著相关性。【结论】确定合理的NDT指标比一味增加指标数量对相关系数的提高影响更大。综合考虑相关系数提升效果以及由此可能增加的测试工作量,预测木材密度和横纹局部抗压强度时建议分别使用“v_(l),F_(m)”和“F_(m),v_(m)”的NDT指标组合。

关键词：木结构无损检测木材密度横纹局部抗压强度线性相关性指标预测

漫画的转型与速写的出场——叶浅予1935年北游之旅考论

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美术 2024年第1期 58-66页

作者：李中诚中央美术学院

叶浅予1935年的北游之旅,既是他速写生涯的标志性节点,同时也是其接触平津文化圈的重要契机。北游之旅正值叶浅予的漫画成名作《王先生》影视化之路肇始,对他在漫画上进行平民化、跨地域的叙事转向具有直观的推动作用。与平津文化圈的交... 详细信息

叶浅予1935年的北游之旅,既是他速写生涯的标志性节点,同时也是其接触平津文化圈的重要契机。北游之旅正值叶浅予的漫画成名作《王先生》影视化之路肇始,对他在漫画上进行平民化、跨地域的叙事转向具有直观的推动作用。与平津文化圈的交往,则为意图寻求艺术转型的叶浅予提供了多元的文化滋养,不仅形塑了他对漫画、速写的新认知,使叶浅予注重速写的现场感知意识与本体艺术价值,更以趋于传统导向的文化环境,促进了他对“传统”在融入大众趣味与世俗审美层面的探索,为“速写漫画”的生成奠定了深厚而鲜活的学理基础。

关键词：叶浅予速写漫画中国画北游之旅平津文化圈

基于改进Hofstetter模型的杨木组分体积分数对其弹性参数的影响规律

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木材科学与技术 2024年第2期38卷 12-19页

作者：王忠铖杨娜李久林北京城建集团有限责任公司北京100088 北京交通大学土木建筑工程学院北京100044

木材的微观结构和组分构成是影响其弹性参数的重要因素,但关于木材组分体积分数变化对其弹性参数影响的研究相对较少。通过引入灰分因素,对Hofstetter木材连续微观力学模型进行改进,并在此基础上分析杨木组分的体积分数变化对其弹性参... 详细信息

木材的微观结构和组分构成是影响其弹性参数的重要因素,但关于木材组分体积分数变化对其弹性参数影响的研究相对较少。通过引入灰分因素,对Hofstetter木材连续微观力学模型进行改进,并在此基础上分析杨木组分的体积分数变化对其弹性参数的影响规律。研究表明:改进的Hofstetter模型可较准确预测杨木的顺纹弹性模量,误差绝对值仅13.71%。结晶纤维素等自身刚度较大的组分体积分数增大时,杨木的弹性模量和剪切模量增幅较大;聚合物网络、无定形纤维素体积分数增大时,泊松比增幅较大;木质素、半纤维素体积分数变化对所有弹性参数的影响均较小。

关键词：杨木改进Hofstetter模型连续介质假设组分弹性参数组分体积分数变化

Neuroprotective effects of subthalamic nucleus high-frequency stimulation on substantia nigra neurons in a Parkinson's disease rat model

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Neural Regeneration Research 2008年第9期3卷 1014-1017页

作者： Yu Ma zhongcheng wang Jianguo Zhang Huanguang Liu Ying Zhang Department of Functional Neurosurgery Beijing Neurosurgical Institute Capital Medical University Beijing 100050 China Department of Neurosurgery Beijing Tiantan Hospital Capital Medical University Beijing 100050 China

BACKGROUND： Deep-brain stimulation has proven to be beneficial in the treatment of Parkinson＇s disease （PD） patients. OBJECTIVE： To investigate the effects of high-frequency stimulation （HFS） to the subthalamic nucleus （STN） on neuronal apoptosis and apoptosis-related gene expression in the substantia nigra pars compacta, and to analyze the neuroprotective effect of HFS-STN. DESIGN, TIME AND SETTING： Neuronal morphology experiments were performed in the Beijing Neurosurgical Institute from May to December in 2005. MATERIALS： Forty healthy, adult, Sprague Dawley rats were used to establish a PD model with a unilateral microinjection of 6-hydroxydopamine into two target areas of the right medial forebrain bundle. 6-hydroxydopamine was purchased from Sigma （USA）; high-frequency electrical stimulator was produced by World Precision Instruments （USA）; Terminal deoxynucleotidyl transferase dUTP nick end labeling （TUNEL） kit was a product of Nanjing Jiancheng Technology Co., Ltd. （China）; and Bcl-2 and Bax protein assay kit were purchased from Wuhan Boster Bioengineering Co., Ltd. （China）. METHODS： Forty rats were randomly divided into three groups. The stimulation group （n = 15） received HFS-STN on the day of PD modeling. The PD model group （n = 15） was used to establish the PD model. The control group （n = 10） was injected with normal saline containing 0.2 g/L ascorbic acid into two areas of the right medial forebrain bundle. MAIN OUTCOME MEASURES： Survival of dopaminergic neurons in the substantia nigra pars compacta was determined using Nissl staining. Apoptosis of dopaminergic neurons was detected using TUNEL techniques. Expression of anti-apoptotic protein, Bcl-2, and pro-apoptotic protein, Bax, were assayed by immunohistochemistry. RESULTS： Following 6-hydroxydopamine injection, the number of substantia nigra pars compacta neurons was reduced in the stimulation and PD model groups, compared to the control group. At 2 and 4 weeks post-surgery, the grey value of Nissl stained images was significantly less in the PD

关键词： apoptosis deep-brain stimulation： high-frequency stimulation Parkinson＇s disease

μ-and m-calpain expression and activity changes following diethylstilbestrol injection in the rat anterior pituitary

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Neural Regeneration Research 2011年第1期6卷 60-65页

作者： Weijiang Zhao Zhongfang Shi Fang Yuan Guilin Li Yazhuo Zhang zhongcheng wang Neuroscience Center Shantou University Medical College Shantou 51504 I Guangdong Province China Beijing Neurosurgical Institute Capital Medical University Beijing 100050 China

Little is known about changes in calpain activity in the pituitary gland. In the present study,μ- and m-calpain activity changes were detected in the rat anterior pituitary following intraperitoneal injection of diethylstilbestrol. Double-immunofluorescence labeling confirmed colocalization of μ- and m-calpain in prolactin-secreting cells （lactotrophs）. Western blot analysis revealed significantly increased expression of both calpains, which accompanied upregulated cytosol and membrane zymographic activities at 12 weeks following diethylstilbestrol injection, compared with rats injected with sunflower oil. Moreover, following estrogen injection, pituitary gland pathological damage gradually worsened with increasing time. Results demonstrated that estrogen regulated calpain expression and activity, and both calpains participated in the pathophysiological processes of the pituitary gland. Ubiquitous calpain expression could serve as an effective target for anti-estrogen drugs.

关键词： diethylstilbestrol ubiquitous calpain anterior pituitary prolactinoma Wistar rats

不同化肥运筹对土壤肥力及水稻产量的影响试验

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南方农业 2024年第3期18卷 135-137页

作者：王中成钦州市钦南区大番坡镇农业农村服务中心广西钦州535000

化肥的过量施用不仅提高了农业生产成本,还造成了土壤板结等问题。为探究施用腐熟有机肥减少传统氮、磷、钾肥施用量的可行性,通过田间试验分析了不同化肥运筹对土壤肥力及水稻产量的影响。结果表明,土壤p H值和土壤容重受肥料影响显著... 详细信息

化肥的过量施用不仅提高了农业生产成本,还造成了土壤板结等问题。为探究施用腐熟有机肥减少传统氮、磷、钾肥施用量的可行性,通过田间试验分析了不同化肥运筹对土壤肥力及水稻产量的影响。结果表明,土壤p H值和土壤容重受肥料影响显著,而土壤有机质含量、碱解氮含量、速效磷含量、速效钾含量,以及水稻产量则受不同施肥处理的显著影响。总体来看,按常规化肥施用量(氮肥225 kg·hm^(-2)、磷肥300 kg·hm^(-2)、钾肥150 kg·hm^(-2))的80%施氮、磷、钾肥并配施腐熟有机肥1 500 kg·hm^(-2),可在不影响水稻产量的同时减少化肥施用量,节省了生产成本,避免了土壤环境恶化。

关键词：化肥运筹腐熟有机肥土壤肥力水稻产量减肥试验

基于高压汞灯荧光显微观测的剩余油定量分析方法

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石油钻探技术 2024年第3期52卷 112-117页

作者：李忠诚鲍志东王洪学张栋中国石油吉林油田分公司勘探开发研究院吉林松原138000 中国石油大学(北京)地球科学学院北京102249 东北石油大学石油工程学院黑龙江大庆163318

为明确不同驱油阶段微观剩余油的分布状态,指导老油田在注水开发后期的剩余油挖潜,选取典型区块不同渗透率级别的岩心进行了驱油试验,采用液氮冷冻技术制作岩心薄片并利用高压汞灯荧光显微镜,分析了饱和油阶段、水驱至模型初见水阶段和... 详细信息

为明确不同驱油阶段微观剩余油的分布状态,指导老油田在注水开发后期的剩余油挖潜,选取典型区块不同渗透率级别的岩心进行了驱油试验,采用液氮冷冻技术制作岩心薄片并利用高压汞灯荧光显微镜,分析了饱和油阶段、水驱至模型初见水阶段和水驱结束后阶段的微观剩余油赋存状态。经过图像处理,细分了剩余油赋存状态,并计算了不同状态剩余油的赋存比例。研究表明,中渗透率岩心水驱主要动用了自由态剩余油,水驱后残存的自由态剩余油较多,可作为继续挖潜对象;低渗透率岩心水驱过程中自由态微观剩余油含量进一步减少,水驱后束缚态的膜状剩余油及半束缚态的喉道状剩余油可作为接替开发对象。高压汞灯荧光显微观测法为剩余油分析提供了一种新的量化方法,可以为老油田的剩余油挖潜提供借鉴。

关键词：高压汞灯荧光微观剩余油定量化分析赋存规律水驱