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大分子振动的一般价力场力常数计算方法的研究
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作者 鄢国森 孙泽民 +1 位作者 肖慎修 薛英 《高等学校化学学报》 SCIE EI CAS 1988年第7期700-705,共6页
本文基于力常数矩阵Fs从UBFF到GVFF的可迁性,提出了一个“由UBFF力常数来限定GVFF力常数”的方法;其次,对“运动学确定力常数法”中A矩阵元排序的规则作了进一步研究。
关键词 力常数 一般 M(CSe(NH_(2))_(2))_(4)^(2+) (M=Pd(Ⅱ) Pt(Ⅱ))
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1989年9月份资本主义市场主要商品月平均价格
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《资本主义市场商品价格》 1989年第10期8-15,共8页
关键词 资本主义市 商品 月平场价
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Techno-economic and Environmental Assessments of SAF from Bioamss:An Review
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作者 MAHMOOD T.M.N.Saeed PANG Shusheng CHEN Qiang 《林产化学与工业》 CAS CSCD 北大核心 2024年第5期29-51,共23页
This review presents a comprehensive techno-economic and life-cycle assessment of sustainable aviation fuel(SAF)production from biomass.The critical need for transitioning towards environmentally sustainable alternati... This review presents a comprehensive techno-economic and life-cycle assessment of sustainable aviation fuel(SAF)production from biomass.The critical need for transitioning towards environmentally sustainable alternatives for liquid fuel and aviation industry is first discussed.Key insights encompass the evolutionary progression of biofuel production from first-generation to second-generation biofuels,with a focus on utilizing non-food sources like woody biomass for enhanced sustainability.Available data from the literature on techno-economic assessments of various SAF production pathways are analyzed including production costs,conversion efficiency,and scalability.Moreover,results of lifecycle assessments associated with different SAF production pathways are presented,providing essential insights for decision-making processes.The challenges of scaling up woody biomass-based SAF production are discussed based on the assessment results,and recommendations are proposed to steer stakeholders towards a greener and more sustainable trajectory for aviation operations. 展开更多
关键词 sustainable aviation fuel woody biomass production costs minimum fuel selling price lifecycle assessment greenhouse gas emissions climate change
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Superposition of dual electric fields in covalent organic frameworks for efficient photocatalytic hydrogen evolution
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作者 Chao Li Shuo Wang +8 位作者 Yuan Liub Xihe Huang Yan Zhuang Shuhong Wu Ying Wang Na Wen Kaifeng Wu Zhengxin Ding Jinlin Long 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期164-175,共12页
Covalent organic frameworks(COFs)are promising materials for converting solar energy into green hydrogen.However,limited charge separation and transport in COFs impede their application in the photocatalytic hydrogen ... Covalent organic frameworks(COFs)are promising materials for converting solar energy into green hydrogen.However,limited charge separation and transport in COFs impede their application in the photocatalytic hydrogen evolution reaction(HER).In this study,the intrinsically tunable internal bond electric field(IBEF)at the imine bonds of COFs was manipulated to cooperate with the internal molecular electric field(IMEF)induced by the donor-acceptor(D-A)structure for an efficient HER.The aligned orientation of IBEF and IMEF resulted in a remarkable H_(2) evolution rate of 57.3 mmol·g^(-1)·h^(-1)on TNCA,which was approximately 520 times higher than that of TCNA(0.11 mmol·g^(-1)·h^(-1))with the opposing electric field orientation.The superposition of the dual electric fields enables the IBEF to function as an accelerating field for electron transfer,kinetically facilitat-ing the migration of photogenerated electrons from D to A.Furthermore,theoretical calculations indicate that the inhomogeneous charge distribution at the C and N atoms in TNCA not only pro-vides a strong driving force for carrier transfer but also effectively hinders the return of free elec-trons to the valence band,improving the utilization of photoelectrons.This strategy of fabricating dual electric fields in COFs offers a novel approach to designing photocatalysts for clean energy synthesis. 展开更多
关键词 Covalent organic framework Internal molecular electric field Internal bond electric field PHOTOCATALYSIS Hydrogen evolution
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Optimal pricing and production decisions in a supply chain with e-marketplace 被引量:1
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作者 何勇 赵林度 何炬 《Journal of Southeast University(English Edition)》 EI CAS 2007年第S1期8-14,共7页
The concept of the e-marketplace is introduced.Considering a supply chain with a single manufacturer who sells a single item in an e-marketplace,an analytical model for the use of the e-marketplace in a supply chain i... The concept of the e-marketplace is introduced.Considering a supply chain with a single manufacturer who sells a single item in an e-marketplace,an analytical model for the use of the e-marketplace in a supply chain is provided.Assuming the market demand is stochastic and price-dependent,the conditions under which the manufacturer and the e-marketplace owner share the market in equilibrium is developed.The existence and uniqueness of the optimal selling price,quantity and transaction percentage are proved.An integrated supply chain is put forward,and then the efficiency of supply chain coordination is studied by comparing the integrated supply chain with the decentralized supply chain.To gain further insights on the theoretical models,extensive simulations are then carried out. 展开更多
关键词 supply chain management E-MARKETPLACE strategy pricing COORDINATION
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乾隆朝徽商在淮盐业经营中的获利估算 被引量:24
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作者 汪崇筼 《盐业史研究》 2000年第1期13-22,共10页
本文是在汪士信先生《乾隆时期徽商在两淮盐业经营中应得、实得利润与流向试析》一文的基础上 ,对当时的盐商获利作一新的尝试性估算 ,以模拟提出代表整个乾隆时期的运商成本单位以及徽商经营淮盐的资金平衡表 ,并对估算结果进行讨论。
关键词 乾隆朝 徽商 淮盐经营 利润 清代 口岸 场价
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Assessment of Direct Eco-value of Liangzi Lake
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作者 封瑛 李兆华 刘化吉 《Agricultural Science & Technology》 CAS 2013年第6期882-885,共4页
[Obective] This study amied to evaluate the direct usage value of Liangzi Lake, like plants and animal resources and water storage value. [Method] It was measured through the market value method. The physical environm... [Obective] This study amied to evaluate the direct usage value of Liangzi Lake, like plants and animal resources and water storage value. [Method] It was measured through the market value method. The physical environment was introduced and the productivity of the lake was investigated both through the literature materials and the investigations. The market value method was clarified in this paper as well as its operation process and the application fields. [Result] Based on the introduction of the current situation in Liangzi Lake, the direct usage value was estimated as 1.32 billion Yuan/year. Plant resources value was 318 million Yuan/year; animal resources value was 675 million Yuan/year; and water storage value was 325 million Yuan/year for the three parts. [Conclusion] This paper will attract more attention to the emphasis of the reasonable development of nature sources. 展开更多
关键词 Valuation assessment Direct usage value Market value method Liangzi Lake
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AlGaInN四元系氮化物分离研究
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作者 黄琨 范广涵 +2 位作者 刘颂豪 李述体 郭志友 《量子电子学报》 CAS CSCD 北大核心 2006年第5期714-718,共5页
氮基四元Ⅲ-Ⅴ族化合物可用于高亮度蓝光LED和高温、大功率及高频电子器件。可以通过改变AlxGayIn1-x-yN组分的大小,得到在与衬底品格匹配的情况下不同的材料禁带宽度,但是由于在给定组分下AlGaInN难以稳定生长。所以应用价力场模型(VFF... 氮基四元Ⅲ-Ⅴ族化合物可用于高亮度蓝光LED和高温、大功率及高频电子器件。可以通过改变AlxGayIn1-x-yN组分的大小,得到在与衬底品格匹配的情况下不同的材料禁带宽度,但是由于在给定组分下AlGaInN难以稳定生长。所以应用价力场模型(VFF)研究它的热动力稳定性,得出了AlGaInN不稳定的二相区间,并且定量讨论两种组分确定的AlGaInN合金的富In区与温度的关系。希望对生长高质量AlGaInN材料起到参考作用。 展开更多
关键词 光电子学 相分离 AlxGayIn1-x-yN LED
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Analysis on China’s Petroleum Imports and Exports in 1st Half of 2005
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作者 Tian Chunrong 《China Oil & Gas》 CAS 2005年第2期48-50,共3页
In the first half of 2005. the import of erude oil increased 4% up of the same period, but the net import of petroleum products including crude oil, oil products, liquefied petroleum gas (LPG) and others declined 7%... In the first half of 2005. the import of erude oil increased 4% up of the same period, but the net import of petroleum products including crude oil, oil products, liquefied petroleum gas (LPG) and others declined 7% of the same period last year. As the oil price in international market continuously climbs up and creates new records, 展开更多
关键词 中国 石油市 进出口贸易 LPG 行情 场价
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Equivalent Doping Transformation Method for Predicting Breakdown Voltage and Peak Field at Breakdown of Epitaxial-Diffused Punch-Through Junction
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作者 何进 张兴 +1 位作者 黄如 王阳元 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第3期256-260,共5页
Based on a new semi empirical analytical method, namely equivalent doping transformation, the breakdown voltage and the peak field of the epitaxial diffused punch through junction have been obtained. The basic prin... Based on a new semi empirical analytical method, namely equivalent doping transformation, the breakdown voltage and the peak field of the epitaxial diffused punch through junction have been obtained. The basic principle of this method is introduced and a set of breakdown voltage and peak field plots are provided for the optimum design of the low voltage power devices. It shows that the analytical results coincide with the previous numerical simulation well. 展开更多
关键词 epitaxial diffused punch through junction breakdown voltage peak field equivalent doping transformation
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Comprehensive Performance Evaluation of Family Farms from the Perspective of Land Transfer——Taking Rudong County as an Example
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作者 孙燕 张云鹏 戴福鑫 《Agricultural Science & Technology》 CAS 2017年第12期2638-2643,共6页
With the reform of agriculture, family farms have become hot spots in the reform of agricultural management system. Taking Rudong County of Jiangsu Province for an example, the land transfer performance of family farm... With the reform of agriculture, family farms have become hot spots in the reform of agricultural management system. Taking Rudong County of Jiangsu Province for an example, the land transfer performance of family farms was evalu- ated using the first hand data from field investigation by building an index system for comprehensive performance evaluation of family farm land transfer covering three dimensions of economy, society and ecology. The results show that land transfer in family farm mode has realized the scale management of land, enhanced the agri- cultural level of science and technology, effectively promoted the structural adjust- ment of agriculture and income increase of farmers, advanced the development of eco-agriculture, and achieved good economic and social performances. However, in the development process of family farms, inputs of agro-chemicals, fertilizers and other agro-products have brought about the eco-environmental problems, which are still worth noting. 展开更多
关键词 Land transfer Comprehensive performance EVALUATION Family farm Rudong County
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求解IO_3^-离子的振动频率
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作者 池贤兴 《温州师范学院学报》 1994年第3期39-44,共6页
本文运用群论知识,采用推广的价键力场的近似[1][5],求出了碘酸锂晶体中IO3-离子的内部正则振动频率的解析表达式。其数值计算结果与实验比较,符合较好。
关键词 正则振动 健力 碘酸锂晶体 碘酸根离子
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Assessing the Economic Value of Vernacular Architecture of Mountain Regions Using Contingent Valuation 被引量:6
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作者 Stella GIANNAKOPOULOU Dimitris DAMIGOS Dimitris KALIAMPAKOS 《Journal of Mountain Science》 SCIE CSCD 2011年第5期629-640,共12页
Human pressure on mountain resources poses certain threats to their natural and man-made environment. Although there are many parameters involved, one of the driving forces behind this situation is the emphasis given ... Human pressure on mountain resources poses certain threats to their natural and man-made environment. Although there are many parameters involved, one of the driving forces behind this situation is the emphasis given so far only to the market value of mountain goods and services, ignoring the true social and environmental costs of using mountain resources. Towards this direction, the use of non-market valuation techniques could prove to be beneficial. Bearing in mind the above remarks, the paper presents an application of the Contingent Valuation Method, which aims at estimating the monetary value of a mountain settlement’s vernacular architecture, namely Metsovo. For this purpose, the survey focuses on Metsovo visitors’ willingness to pay a single annual voluntary contribution to an institution that would be founded in order to undertake all necessary actions required to preserve the town’s traditional character. The results are very promising and indicate that vernacular architecture holds a significant economic value that could justify the implementation of appropriate policies towards the protection of vernacular settlements in mountain areas. 展开更多
关键词 Non-market valuation Vernacular architecture Contingent valuation
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Eco-compensation of Wetlands in Yellow River Delta of Shandong Province,China 被引量:3
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作者 HAN Mei CUI Jinlong +2 位作者 HAO Zhen WANG Yi WANG Renqing 《Chinese Geographical Science》 SCIE CSCD 2012年第1期119-126,共8页
Wetlands play an important ecological role and provide many functions for people, yet wetlands are cur- rently decreasing and deteriorating. The ability to calculate an economic value for the loss of wetlands is becom... Wetlands play an important ecological role and provide many functions for people, yet wetlands are cur- rently decreasing and deteriorating. The ability to calculate an economic value for the loss of wetlands is becoming in- creasingly important for policy makers. In this study, remote sensing, field investigations, department visits, and other methods were used to survey wetland types, assess wetland area changes, and calculate wetland economic value. Mar- ket value loss and ecological ftmction value loss, caused by reduction of wetland area and environmental pollution were calculated using commonly accepted methods of market valuation, ecological valuation, environmental protection investment cost analysis, and outcome parameters. According to market value loss and ecological function value loss, preliminarily fund allocation for wetland and ecological compensation was calculated. This will provide an important reference for future Yellow River Delta eco-compensation studies. 展开更多
关键词 Yellow River Delta WETLAND eco-compensation compensation standard
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Improving the Size and Market Value of an Underutilised Yam (Dioscorea esculenta) in Ghana: Implications for Crop Breeding and Production Choices 被引量:2
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作者 Kwamina Banson Kenneth Danso 《Journal of Life Sciences》 2013年第7期732-741,共10页
Yam, Dioscorea esculenta which is a high value commodity is a threatened species in Ghana, due to several factors including neglect on the part of science, technology, research and development. Different doses of radi... Yam, Dioscorea esculenta which is a high value commodity is a threatened species in Ghana, due to several factors including neglect on the part of science, technology, research and development. Different doses of radiation were use to improve the size and market value of D. esculenta to promote it effective use and enhance effective conservation. We observed through repeated experiments that irradiation of yam planting material at 40 Gy gave the best results producing a M1 generation with a decreased number of tubers but with an increased tuber size per vine. Some yam characteristics are valued more than others, and prices vary across species, time, and market sites. Tuber weight exhibits an increasing marginal value and price per kilogram increases above an optimum size; therefore, yam producers and dealers derive additional reward from extra-large tubers. We conclude that, to effectively access and benefit from urban markets, producers should focus on the improved size and conical shaped-tubers, which are easy to process and meet the aesthetic qualities preferred by urban consumers. The implications for research on improved variety development to reduce poverty and for crop and resource management practices are drawn. 展开更多
关键词 Dioscorea esculentus MARKET MUTATION PRODUCTIVITY threatened species.
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Suggestions on the Effective Development of Shale Gas in China 被引量:2
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作者 Cao Yan Yang Kefeng +1 位作者 Jing Keyao Hu Yan 《China Oil & Gas》 CAS 2018年第4期18-25,共8页
Shale gas is a practical resource with great potential that could be economically explored and developed in the near future. It has been commercially developed in North America and other places. Featuring a vast distr... Shale gas is a practical resource with great potential that could be economically explored and developed in the near future. It has been commercially developed in North America and other places. Featuring a vast distribution, a low abundance,unfavorable reservoir conditions, ultra-low permeability and a fast production decline, shale gas is more difficult to develop than conventional natural gas, as it needs advanced drilling and completion technology to develop. During the early stage of shale gas exploration and development, the United States offered enterprises necessary incentives such as tax reductions and exemptions and subsidies to achieve sustainable shale gas development and encourage technological progresses. By comparing the state of China's shale gas development with that of the US' in terms of geological conditions, production technology,market price, tax relief, subsidy periods and amount, this paper intends to put forward related suggestions for the effective development of shale gas according to the current status of development. 展开更多
关键词 Unconventional resource Shale gas Effective development Subsidy period SUBSIDY SUGGESTION
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Price linkage between Chinese and international nonferrous metals commodity markets based on VAR-DCC-GARCH models 被引量:16
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作者 岳意定 刘笃池 徐珊 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期1020-1026,共7页
Using VAR-DCC-GARCH model,the literature on commodity price was extended by exploring the co-movement between Chinese nonferrous metal prices and global nonferrous metal prices represented by the nonferrous metal pric... Using VAR-DCC-GARCH model,the literature on commodity price was extended by exploring the co-movement between Chinese nonferrous metal prices and global nonferrous metal prices represented by the nonferrous metal prices from London Metal Exchange(LME).The results show that LME nonferrous metals prices still have a greater impact on Chinese nonferrous metals prices.However,the impact of Chinese nonferrous metals prices on LME nonferrous metals prices is still weak except for lead price.The co-movement of nonferrous metal prices between LME and China presents hysteretic nature,and it lasts for 7-8trading days.Furthermore,the co-movement between LME nonferrous metals prices and Chinese nonferrous metals prices has the characteristics of time-varying,and the correlation of lead prices between LME and China is the more stable than all other nonferrous metals prices. 展开更多
关键词 price linkage nonferrous metals commodity prices Chinese metals commodity market LME CO-MOVEMENT VAR model DCC-GARCH model
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Recovery of Foreign Interest Rates from Exchange Binary Options 被引量:1
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作者 M. Mitsuhiro Y. Ota 《Computer Technology and Application》 2015年第2期76-88,共13页
One of most challenging problems from applying the Black-Scholes model to financial derivatives, is reconciling the deviation between the expected and observed values. This study derives an extension of the Black-Scho... One of most challenging problems from applying the Black-Scholes model to financial derivatives, is reconciling the deviation between the expected and observed values. This study derives an extension of the Black-Scholes model and recovers the real drift of binary call options from their market prices. For space-dependent real drift, we obtain stable linearization and an integral equation. We also find that using market prices of options with different strike prices enables us to identify the term structure of the real drift. Results demonstrate that our new approach can confirm the existence of arbitrage opportunities in a binary option transaction. 展开更多
关键词 Inverse problem binary option real drift arbitrage opportunities Black-Scholes model.
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Fair Valuation Issues and the Subprime Mortgage Debacle: Could Generally Accepted Accounting Principles Underlying the Historical Cost Method Have Prevented the Crisis? 被引量:1
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作者 Constance Crawford Corinne Crawford Raymond Rigoli 《Journal of Modern Accounting and Auditing》 2011年第11期1223-1228,共6页
There are three primary methodologies employed to determine real estate value in the appraisal industry: the cost approach, the sales approach and the income approach. The definition of market value is defined as: ... There are three primary methodologies employed to determine real estate value in the appraisal industry: the cost approach, the sales approach and the income approach. The definition of market value is defined as: "a type of value, stated as an opinion that includes a set of assumptions concerning the market". Unfortunately, untrained and unlicensed appraisers provided opinions using primarily the sales approach or market data approach and virtually ignored the other two methodologies. The ensuing game of "Can You Top This" resulted in creating an out-of-control real estate market driven by unregulated fiduciaries as appraisers. 展开更多
关键词 subprime mortgage fair valuation accounting mark-to-market accounting
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Hedonic price analysis of urban housing:An empirical research on Hangzhou,China 被引量:2
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作者 温海珍 贾生华 郭晓宇 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第8期907-914,共8页
The hedonic price model is widely applied to study the urban housing market because of the heterogeneity of housing products. Literature indicated that the hedonic price theory mainly includes two parts: Lancaster’s ... The hedonic price model is widely applied to study the urban housing market because of the heterogeneity of housing products. Literature indicated that the hedonic price theory mainly includes two parts: Lancaster’s partiality theory and Rosen’s characteristic market equilibrium analysis. This paper chose 18 characteristics as independent variables and set up a linear hedonic price model for Hangzhou City. The model was tested with 2473 housing samples and field survey data of 290 housing commu-nities. This research found that 14 out of 18 characteristics had significant influence on housing price. They were classified into 5 groups according to their impact degree. 展开更多
关键词 Housing price Housing characteristics Hedonic price model
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