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1.
能源合作是“一带一路”战略的重要内容,我国作为世界最大的能源消费国,每年要从世界各地进口大量能源资源特别是油气资源,并且对外依存度逐年攀升,油气安全问题令人担忧。实施“一带一路”战略,加强与沿途国家的能源合作,能为我国能源安全提供保障。天然气作为清洁、高效能源,对缓解能源短缺和环境污染具有重要作用,在世界能源消费结构中占据重要地位。通过对“一带一路”主要能源国家天然气产量、消费量、进/出口贸易量数据的搜集与分析,明确了主要国家天然气供需及贸易特点,并且提出了一些在“一带一路”合作框架下更有力地发展我国天然气行业的建议。  相似文献   

2.
The objectives of this study are to investigate the levels of noise pollution in some hospitals in Taiwan and to study the effects of noise pollution on the physiological and psychological reactions and annoyance response of medical care staff, patients and visitors in these hospitals. An instrument for the measurement of sound level was used and a self-answered survey questionnaire on noise pollution was administered. Results showed that the daily average sound levels measured inside these hospitals during daytime were between 52.6 and 64.6 decibels. These are higher than the current daytime environmental noise limit of 50 decibels in Taiwan. Most nursing staff members expressed that “talking of visitors or patient’s family members” is the major source of noise inside the wards, whereas “talking of visitors or patient’s family members” and “children playing” are the two major noise sources outside the wards. However, most patients or visitors claimed that “doors opening or closing” and “patients moaning or crying” are the two major sources of noise inside the wards. “Footsteps,” “renovation of hospitals,” “talking of visitors or patient’s family members,” “shouting of nursing staff” and “doors opening or closing” are the five major noise sources outside the wards. To conclude, noise pollution inside and outside the wards either directly or indirectly affects, in a simultaneous manner, the subjective perception of noise, emotions, physiology and experience of noise inside and outside the wards of both the medical care staff and the patients and visitors.  相似文献   

3.
以“创新驱动、持续发展”为主题的2014中国国际矿业大会于10月底召开。大会期间,国内外专家学者和业内人士围绕当前全球经济和矿业形势进行了深入交流,其中包罗了各项重点和热点议题,而2014年国际矿产勘查形势与技术的革新与发展则是矿业领域的焦点问题之一。随着经济社会对矿产资源的旺盛需求,全球矿产勘查形势不断变化,勘查投入继续增长,高新技术广泛应用并成为矿产勘查的先导。矿产勘查重新受到国家和社会的广泛关注,矿产勘查进入了多元化合作、技术推动、繁荣发展的新时期。  相似文献   

4.
Based on the dynamic analysis and research of pollution risk of groundwater sources, this paper creates the dynamic assessment method of pollution risk of groundwater source area under the theory of “source-pathway-receptor”, and applies this method to one typical fissure karst groundwater source area in northern China. Following the 30-year petroleum pollutant migration simulation and pollution risk assessment of groundwater source area, this study finds that the very high risk zone is mainly located in Q Petrochemical Company and the surrounding area and the area adjacent to River Z. Within this period of thirty years, the pollution risk of groundwater source area has showed a dynamic trend that features an inverted “V” shape. The ratio of very high risk zone to the total area will be 18.1%, 17.47% and 16.62% during the tenth year, the twentieth year and the thirtieth year separately, and will reach the highest level of 19.45% during the fifteenth year. Meanwhile, the vertical migration distance of pollutant centre concentration changed from the surface soil at the outset to the deepest point of about 250 meters underground during the tenth year. The results of this risk assessment indicate the dynamic feature of pollution risk. The dilution, degradation and migration of petroleum pollutants in groundwater system contribute to an ultimate decline in pollution risk.  相似文献   

5.
Lv  Hong  Guan  Xinjian  Meng  Yu 《Natural Hazards》2020,103(2):1823-1841

The extreme precipitation events caused by climate change and the rapid development of urbanization have brought hidden flood risks to the cities. This paper comprehensively considered two major factors of vulnerability of urban flood-bearing and disaster prevention and mitigation (DPAM) capacity and built a comprehensive evaluation index system for urban flood-bearing risks. Secondly, a combined model consisted of composite fuzzy matter-element and entropy weight model was constructed to calculate the comprehensive risk indicator. Finally, the Zhengzhou City was taken as an example, the comprehensive indices of urban flood-bearing risk from 2006 to 2015 were evaluated. The results showed that the comprehensive risk of Zhengzhou City was generally on a slow upward trend, from II level (moderate-risk) in 2006 to III level (secondary high-risk) in 2015, which was mainly due to the mismatch between the rapid development of urbanization and the slow improvement of DPAM capabilities. This paper is expected to provide scientific reference and technical support for urban flood disaster prevention and sponge city construction.

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6.
通过对莫桑比克社会、自然地理及地质矿产概况的梳理,基本掌握了中资及其他企业对钛锆砂矿资源掌控及开发现状.同时,从中莫经贸互动、中莫地调机构的合作基础、外商投资概况和投资条件等方面对莫桑比克矿业投资环境进行分析.研究认为莫桑比克钛锆砂矿资源丰富,投资环境较好,中资企业介入良好.应继续加强中莫交流与合作,服务于"一带一路"...  相似文献   

7.
This article considers the Navajo Green Jobs effort of 2009, an attempt to “transition” energy production from coal to wind and solar for the largest tribe in the United States, the Navajo Nation. Through ethnographic “revisits,” in 2008 and 2013, I argue that Navajo Green Jobs contained two problematic hybrid neoliberal assumptions about governance and development: (1) it decentered governing authority from the tribe to “the community” while undermining the legitimacy of the tribal government, and (2) it promoted private entrepreneurship over public investment as the vehicle for energy transition. Ultimately, the Navajo Nation rejected Navajo Green Jobs and re-appropriated its temporal language in order to justify a reinvestment in coal in the form of a new energy company, NTEC. This article concludes that consideration of the spatial and social embedded nature of energy production is vital for understanding energy transitions today.  相似文献   

8.
Ancient geosynclinal coastal deposits, preserved and exposed for present-day examination, probably represent interior—and hence protected—shores, and were therefore characterized by low-to-moderate breaker energy levels, as is the modern Gulf of Mexico. Modern low-energy beach sand size distributions are distinguished by an inflection, here called the surf “break”, formed by a winnowing or statistical filtering process, by the breakers, in the finer sizes. The result is a two-segment curve having an intersection in many cases not far from 1.5 phi. If the energy level is very low, a tail of fines may be added, producing a three-segment curve having two inflection points. Along high energy beaches, the surf “break” occurs at such large grain sizes that it cannot be preserved in sand; whether or not it can be recognized in gravel is not known. Ancient sandstones which represent the breaker zone, along a low-to-moderate energy coast, should also exhibit the surf “break”. The Lyons Sandstone, a known Permian beach deposit, provides an example. Other examples are cited. Any useful indicator of the shoreline position, in lithified rocks, should have three characteristics: ease of recognition, high reliability, and strong probability of preservation. The surf “break” scores reasonably well on all three points. Hence it may be an important key to paleogeography. Nevertheless, there still remains a question inasmuch as certain river sands have similar inflections. Whether these kinks were inherited from near-by, but older, beach deposits, or were formed by stream action, is not known. The reliability of the surf “break” is estimated at 80% or better, except for the case where near-shore sands, of whatever age, are reworked briefly by running water.  相似文献   

9.
Shi  X. S.  Zeng  Yiwen  Shi  Congde  Ma  Zhanguo  Chen  Wenbo 《Acta Geotechnica》2022,17(9):3839-3854

Gap-graded granular soils are used as construction materials worldwide, and their hydraulic conductivity depends on their relative content of coarse and fine grains, initial conditions, and particle shape. In this study, a series of constant head hydraulic conductivity tests were performed on gap-graded granular soils with different initial relative densities, fine contents, and particle shapes. The test results show that the hydraulic conductivity decreases with an increase in fine fraction and then remains approximately constant beyond the “transitional fine content.” The role of the structural effect on the hydraulic conductivity is different from that on the mechanical properties (such as stiffness and shear strength). This can be attributed to the degree of filling within inter-aggregate voids, disturbance of soil structure, and densified fine bridges between coarse aggregates. The equivalent void ratio concept was introduced into the Kozeny–Carman formula to capture the effect of fines (aggregates) on the “coarse-dominated” (“fine-dominated”) structure, and a simple model is proposed to capture the change of hydraulic conductivity of gap-granular soils. The model incorporates a structural variable to capture the effect of fines on “coarse-dominated” structure and coarse aggregates on “fine-dominated” structure. The performance of the model was verified with experimental data from this study and previously reported data compiled from the literature. The results reveal that the proposed model is simple yet effective at capturing the hydraulic conductivity of gap-graded granular soils with a wide range of fine contents, initial conditions, and particle shapes.

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10.
This study uses the total-factor energy productivity change index (TFEPCH) to investigate the changes in energy productivity of construction industry for 30 provincial regions in China from 2006 to 2015, adopting the improved Luenberger productivity index combined with the directional distance function. In addition to traditional economic output indicator, this study introduces building floor space under construction as a physical output indicator for energy productivity evaluation. The TFEPCH was decomposed into energy technical efficiency change and energy technical progress shift. Results indicate that, first, energy productivity of China’s construction industry decreased by 7.1% annually during 2006–2015. Energy technical regress, rather than energy technical efficiency, contributed most to the overall decline in energy productivity of China’s construction industry. Second, energy productivity in the central region of China decreased dramatically, by a cumulative sum of approximately 77.1%, since 2006, while energy productivity in the eastern and western regions decreased by over 54.3 and 65.3%, respectively. Only two of the 30 provinces considered—Hebei and Shandong—improved their energy productivity during 2006–2015. The findings presented here provide a basis for decision-making and references for administrative departments to set differentiated energy efficiency goals and develop relevant measures. Additionally, the findings are highly significant for energy and resource allocation of Chinese construction industry in different regions.  相似文献   

11.
Jiao  Kaituo  Han  Dongxu  Wang  Daobing  Chen  Yujie  Li  Jingfa  Gong  Liang  Bai  Bofeng  Yu  Bo 《Computational Geosciences》2022,26(5):1167-1187

Thermal-hydro-mechanical (THM) coupled fracture propagation is common in underground engineering. Rock damage, as an inherent property of rock, significantly affects fracture propagation, but how it influences the THM coupled fracturing remains stubbornly unclear. A pore-scale THM coupling model is developed to study this problem, which combines the lattice Boltzmann method (LBM), the discrete element method (DEM), and rock damage development theory together for the first time. This model can more accurately calculate the exchanged THM information at the fluid-solid boundary and fluid conductivity dependent on fracture and rock damage. Based on the developed model, the synergistic effect of injected temperature difference (fluid temperature below rock temperature) and rock damage (characterized by the parameter “critical fracture energy”, abbreviated as “CFE”) on fracture propagation of shale are investigated particularly. It is found that: (1) the generation of branched cracks is closely related to the temperature response frontier, and the fracture process zone of single bond failure increases in higher CFE. (2) through the analysis of micro failure events, hydraulic fracturing is more pronounced in the low CFE, while thermal fracturing displays the opposite trend. The fluid conductivity of fractured rock increases with a higher injected temperature difference due to the more penetrated cracks and wider fracture aperture. However, this enhancement weakens when rock damage is significant. (3) in the multiple-layered rock with various CFEs, branched cracks propagating to adjacent layers are more difficult to form when the injection hole stays in the layer with significant rock damage than without rock damage.

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12.
Kiribati, Tuvalu, Marshall Islands, the Maldives and other small island developing states in the Pacific are often incorrectly called “sinking islands.” With their highest points just a few meters above sea level, they face adverse impacts from climate change and especially sea level rise, which can cause them to disappear entirely or make their territory uninhabitable. After rather frustrating negotiations on other fora, the representatives of those states asked the UN Security Council to deal with their perilous situation in 2007. On the one hand, some countries used scientific argumentation to justify the introduction of this new security agenda. On the other hand, prominent UNSC members such as China and Russia, supported mainly by rapidly developing large countries, rejected it, arguing that the Security Council did not have the expertise to solve environmental problems. Since then the islands have echoed their plight to the UNSC in 2011 and 2015. This paper determines what roles individual countries ascribe to “experts” and “science” during UNSC negotiations. It examines how the authority of “experts” was exploited, which allowed certain countries to strike the issue of those islands from the UNSC agenda by calling for a more “scientific approach,” while others used “science” to widen the concept of security. The analysis of empirical data confirms the theory of Berling's three modalities when referring to science. Those modalities can be further extended by Foucault's conception of “will to truth” as a method of exclusion, and Chandler's theory of “empire in denial” as a way of evading responsibility, while maintaining power.  相似文献   

13.
Fan  Tijun  Luo  Ruiling  Xia  Haiyang  Li  Xiaopeng 《Natural Hazards》2014,75(2):319-332

China’s petrochemical industries are playing an important role in China’s economic development. However, the industries consume large amounts of energy and have become primary sources of carbon emission. In this paper, the change in carbon emissions from China’s petrochemical industries between 2000 and 2010 was quantitatively analyzed with the Log-Mean Divisia Index method, which was decomposed into economic output effect, industrial structural effect and technical effect. The results show that economic output effect is the most important factor driving carbon emission growth in China’s petrochemical industries; industrial structural effect has certain decrement effect on carbon emissions; adjustment of industrial structure by developing low-carbon emission industrial sectors may be a better choice for reducing carbon emissions; and the impact of technical effect varies considerably without showing any clear decrement effect trend over the period of year 2000–2010. The biggest challenge is how to make use of these factors to balance the relationship between economic development and carbon emissions. This study will promote a more comprehensive understanding of the inter-relationships of economic development, industrial structural shift, technical effect and carbon emissions in China’s petrochemical industries and is helpful for exploration of relevant strategies to reduce carbon emissions.

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14.
Liu  Liang  Li  Lianshui 《Natural Hazards》2021,107(3):2463-2486

Technical change has a pivotal role to play in low-carbon development. Recent research has offered different insights regarding the effect of technical change on CO2 emissions but ignored the bias of technical changes which lead to changes in CO2 emissions. To fill the gap, this paper uses the 2008 to 2015 provincial-level data on China’s 22 industrial sub-sectors to investigate both the effect of directed technical change on CO2 emissions and its heterogeneity. We find that the technical change in most industrial sectors in China was capital-biased, although a labor-biased trend was evident. Labor-biased technical change is conducive to CO2 reduction, while capital-biased technical change has the opposite effect. Moreover, this effect is different by developmental periods, industries, and regions. Therefore, we propose that the government promotes labor-biased technical change based on the differentiated characteristics.

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15.

The pre-hospital emergency staff played a key role in transferring the injured patients to health centers. Usually, they reported changes in their decisions on the transfer of non-traumatic patients to hospitals. So, this study was aimed to explore the reasons for unnecessarily requesting an ambulance by non-traumatic patients after the acute responding-to-earthquake phase. This study was a qualitative study that data were analyzed by content analysis approach. Participants were eleven pre-hospital emergency technicians. Data were collected by three sessions of focus group discussion. Data analysis was led to emergence of a main theme: “feeling urgency due to turmoil and uncertainty.” This theme illustrates the basic approach of the inhabitants of the earthquake-stricken region when unnecessarily requesting an ambulance. This theme was derived from two main categories of “turbulent and uncertain conditions” and “psychological turmoil.” The category of “turbulent and uncertain conditions” was comprised of three subcategories: “unreliable care,” “inadequate facilities” and “turbulent living conditions.” The category of “psychological turmoil” was comprised of three subcategories: “psychological turmoil in survivors,” “healthcare providers deciding under pressure” and “turmoil in providing psychological and psychiatric services.” Ambulance dispatch may be unnecessarily performed owing to turbulent and unsure conditions and psychological turmoil in earthquake-stricken people and pre-hospital emergency staff. Providing earthquake-stricken people with psycho-medical services in their place of residence can significantly reduce the workload of pre-hospital emergency staff and consequently that of hospital staff and therefore save time and treatment costs and increase the quality of health services provided for the injured.

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16.
Heavy metal pollution in the surficial sediments derived from the estuary in Daliao River and Yingkou Bay is investigated to assess environmental quality, pollution level, bioavailability and toxicity. The ranges of Pb, Co, Zn and Cu concentrations in the surficial sediments are: 16.57–39.18, 3.61–16.02, 16.53–39.18, 2.77–43.80 mg/kg. Results of the geoaccumulation index (I geo) show that the pollution levels of four metals are in the “unpolluted” class except for Pb in 15 sampling sites. The pollution level of the study area assessed by pollution load index (PLI) shows that except for the moderately polluted region of sites 1, 2, 3, 8, 12 and 13, other sites belong to unpolluted state. The sequence of pollution extent of different heavy metals is: Pb > Zn > Co > Cu. At all sampling sites, the grades of potential ecological risk of Co, Cu, Pb and Zn are “light”. The order of potential ecological risk is: Pb > Co > Cu > Zn. Sequential extraction of the metals indicates that the states of Pb, Cu, Co and Zn in the sediment are relatively stable at most sites of the estuary in Daliao River and Yingkou Bay, which means that there is a low source of pollution arriving in this area. While only at several sites, Co, Pb and Zn are labile, which are considered as anthropogenically originated.  相似文献   

17.
The analysis of various factors influencing mineral availability documents future short-and long-term mineral-commodity supply trends. The lifetime of reserves, the development of the relative importance of production centres and the forecasting of the depletion of a resource base are mainly geological factors, although the category “reserves”, in contrast to “resources”, is determined by technical and economical aspects. These three factors govern the short-and long-term supply of mineral commodities. The intensity-of-use factors and the growth rate of consumption are variables related to the demand of mineral commodities. They influence the decision of companies for certain commodities as targets for exploration and investment in production centres. Both factors control the short-to medium-term mineral supply. Finally, the lead time to production is a technical variable, although influenced by ore deposit type, and controls short-term mineral availability.  相似文献   

18.
Yin  Jia-Yin  Cao  Yun-Fei  Tang  Bao-Jun 《Natural Hazards》2019,95(1-2):343-362

China has become the world’s largest carbon emitter since 2007; thus, reducing future emission has become an arduous task. Calculating energy efficiency fairly is paramount for formulating energy policies, given the different development levels of provinces. This study employed a three-stage data envelopment analysis model that considered environmental constraints to evaluate the energy efficiency of China’s 30 provinces in 2015 and redefined traditional energy efficiency as energy environment efficiency which calculated under environmental constraints. Different factors, such as urban development level and industrial structure in relation to energy environment efficiency, were analyzed. Three main results were obtained. First, the average energy environment efficiency in 2015 was only 0.73, which showed that China has roughly 30% capacity for improvement in the future. Second, stochastic frontier analysis demonstrated that the industrial structure, energy consumption structure, and central heating systems exerted negative impacts, and the level of city design and the degree of openness exerted positive effects on energy environment efficiency. Third, capital, manpower, and the extent of industrial concentration in central and western regions should be increased to improve China’s energy environment efficiency.

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19.
Definition of “measured” and “indicated” resources tend to be vague. Yet, the calculation of such categories of resources in a mineral deposit calls for specific technical criteria, the selection of which depends upon the method of evaluation. This paper discusses how a geostatistical methodology provides the technical criteria required to classify reasonably assured resources by levels of assurance of their existence. A preliminary discussion concludes that the reasonably assured resources of a mineral deposit should be classified locally as in the traditional approach. However, the size of local volumes should not correspond to the elementary grid unit of drill holes but if possible to the minimum unit of selection that can be supported by the chosen mining method. The “level of confidence” of the reasonably assured resources can be quantitatively represented and determined by the estimation variance, one of the most important tools of geostatistics.  相似文献   

20.
《China Geology》2018,1(2):273-285
Geothermal energy is a precious resource, which is widely distributed, varied, and abundant. China has entered a period of rapid development of geothermal energy since 2010. As shallow geothermal energy promoting, the depth of hydrothermal geothermal exploration is increasing. The quality of Hot Dry Rock (HDR) and related exploratory technologies are better developed and utilized. On the basis of geothermal development, this paper reviews the geothermal progress during the “12th Five-Year Plan”, and summarizes the achievements of hydrothermal geothermal and hot dry rocks from geothermal survey and evaluation aspects. Finally, the authors predict the development trend of the future geothermal research to benefit geothermal and hot dry rock research.  相似文献   

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