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41.
A lack of clear political commitment together with confusing rules and enforcement often characterize the institutional context of policy implementation and regulatory compliance in developing countries. By connecting such contextual features to existing models of policy implementation and regulatory compliance, we examine how regulatory factors are related to basic and proactive corporate environmental management practices in the Pearl River Delta region in China. Drawing on data derived from both a survey and in‐depth interviews, we show that a perception of clear political commitment to environmental protection across multiple government levels and units is positively associated with business efforts in basic environmental practices, regardless of the specific enforcement intensity. Nevertheless, a perception of clear political commitment is not related to proactive environmental practices. Conversely, a perception of policy ambiguity, in the form of confusing regulatory standards and enforcement, is negatively associated with corporate efforts in both basic and proactive environmental practices; yet, intensive inspections mitigate these negative associations with policy ambiguity.  相似文献   
42.
In the early days of the Cold War, Syria was the first Arab country where former officers of the German Wehrmacht played an active role as military advisors. This was due, in part, to the fact that Germany was not burdened by its past political relations to Arab states for, in contrast to the Western powers, Germany which had never had territorial ambitions in the Near East. Even in the very early stages, German advisors contributed considerably to the development of Syria's armed forces and military intelligence. The advisory activities of German experts became even more intensive as a result of increased trade between the two countries; however, in 1956 the political situation in Syria worsened and the country began moving towards the Eastern Bloc putting an end to the non-official activities of German military advisors.  相似文献   
43.
刘向作为《战国策》的编定者,对该书总体性质的形成有着深刻的影响。以往质疑刘向部属归类的讨论,未能在此前提之下进行讨论。由此,论者往往过度聚焦于书中具体篇章所体现的子书色彩,却游离了最应着力审视的全书总体性质。事实上,通过审视该书编辑体例、编辑目的,以及刘向对其在部属归类上的斟酌取舍,不难得出《战国策》总体性质是史料汇编类文献的结论。概言之,刘向对《战国策》的部属归类是合理的。这也展现了一代文献学大家卓越的专业眼光。  相似文献   
44.
司马迁记述人物的成就有诸多方面,其中"成功地刻画特定历史环境的人物形象"尤其值得我们深入总结和大力阐释。《伍子胥列传》、《魏公子列传》、《袁盎晁错列传》等名篇,不仅展现了这些人物生动感人的性格、神采,而且深刻地反映出他们所处的不同时代的特点,因而为我们提供了撰写历史人物传记的成功典范。我们要认真借鉴《史记》的成功经验,努力实现对传统史学精华的创造性转化和创新性发展,不断探求在当今历史书写中如何做到既能生动地刻画人物的活动、性格、气质,又能凸显其所处的时代特点,从而有效地克服历史著作平淡乏味的缺陷,使我们撰写的史书更能受到大众的欢迎。  相似文献   
45.
Accurate simulation of multiphase flow in fractured porous media remains a challenge. An important problem is the representation of the discontinuous or near discontinuous behaviour of saturation in real geological formations. In the classical continuum approach, a refined mesh is required at the interface between fracture and porous media to capture the steep gradients in saturation and saturation‐dependent transport properties. This dramatically increases the computational load when large numbers of fractures are present in the numerical model. A discontinuous finite element method is reported here to model flow in fractured porous media. The governing multiphase porous media flow equations are solved in the adaptive mesh computational fluid dynamics code IC‐FERST on unstructured meshes. The method is based on a mixed control volume – discontinuous finite element formulation. This is combined with the PN+1DG‐PNDG element pair, which has discontinuous (order N+1) representation for velocity and discontinuous (order N) representation for pressure. A number of test cases are used to evaluate the method's ability to model fracture flow. The first is used to verify the performance of the element pair on structured and unstructured meshes of different resolution. Multiphase flow is then modelled in a range of idealised and simple fracture patterns. Solutions with sharp saturation fronts and computational economy in terms of mesh size are illustrated.  相似文献   
46.
47.
L. Jiang  W. Pan  C. Cai  L. Jia  L. Pan  T. Wang  H. Li  S. Chen  Y. Chen 《Geofluids》2015,15(3):483-498
Permian hydrothermal activity in the Tarim Basin may have been responsible for the invasion of hot brines into Ordovician carbonate reservoirs. Studies have been undertaken to explain the origin and geochemical characteristics of the diagenetic fluid present during this hydrothermal event although there is no consensus on it. We present a genetic model resulting from the study of δ13C, δ18O, δ34S, and 87Sr/86Sr isotope values and fluid inclusions (FIs) from fracture‐ and vug‐filling calcite, saddle dolomite, fluorite, barite, quartz, and anhydrite from Ordovician outcrops in northwest (NW) Tarim Basin and subsurface cores in Central Tarim Basin. The presence of hydrothermal fluid was confirmed by minerals with fluid inclusion homogenization temperatures being >10°C higher than the paleo‐formation burial temperatures both in the NW Tarim and in the Central Tarim areas. The mixing of hot (>200°C), high‐salinity (>24 wt% NaCl), 87Sr‐rich (up to 0.7104) hydrothermal fluid with cool (60–100°C), low‐salinity (0 to 3.5 wt% NaCl), also 87Sr‐rich (up to 0.7010) meteoric water in the Ordovician unit was supported by the salinity of fluid inclusions, and δ13C, δ18O, and 87Sr/86Sr isotopic values of the diagenetic minerals. Up‐migrated hydrothermal fluids from the deeper Cambrian strata may have contributed to the hot brine with high sulfate concentrations which promoted thermochemical sulfate reduction (TSR) in the Ordovician, resulting in the formation of 12C‐rich (δ13C as low as ?13.8‰) calcite and 34S‐rich (δ34S values from 21.4‰ to 29.7‰) H2S, pyrite, and elemental sulfur. Hydrothermal fluid mixing with fresh water in Ordovician strata in Tarim Basin was facilitated by deep‐seated faults and up‐reaching faults due to the pervasive Permian magmatic activity. Collectively, fluid mixing, hydrothermal dolomitization, TSR, and faulting may have locally dissolved the host carbonates and increased the reservoir porosity and permeability, which has significant implications for hydrocarbon exploration.  相似文献   
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49.
生态问题是当前政府和学术界都十分关注和重视的问题,也是关乎当今和子孙后代生存发展的重大问题。贵州的世居少数民族在漫长的社会、生产、生活的实践中,形成了本民族的生态知识和传统生态理念。本文着重从贵州少数民族的传统生态理念:和谐理念、保护理念、风水理念等方面进行论述。  相似文献   
50.
2010年11月,陕西省子洲县裴家湾镇关王岔村出土了6件青铜容器,包括尊、瓿、盘、觚、鼎、提梁卣各1件。本文通过对铜器上遗留的工艺痕迹进行肉眼观察,对铜器的铸型设计、芯撑情况、浇注位置等铸造工艺环节以及铸后加工的细节进行了初步的判断和复原,指出该批铜器的铸造工艺与安阳出土的殷墟前期同类器物基本相同,这一结果对认识和揭示这批青铜器的学术价值具有重要的意义。  相似文献   
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