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1.
党的十九届四中全会站在党和国家事业全局和战略高度,立足当前,着眼长远,专门研究审议了坚持和完善中国特色社会主义制度、推进国家治理体系和治理能力现代化的重大问题,从坚定制度自信和推进制度创新的结合上系统回答了“坚持和巩固什么、完善和发展什么”这个重大政治问题,第一次集中概括了中国特色社会主义制度有机联系、相辅相成、汇聚整体的显著优势,系统阐述了由根本制度、基本制度、重要制度构成的层次清晰、全面系统的科学制度体系,明确提出了推进我国制度建设和国家治理的指导思想、总体要求、总体目标、战略途径和重大举措。这次全会通过的《中共中央关于坚持和完善中国特色社会主义制度推进国家治理体系和治理能力现代化若干重大问题的决定》(以下简称《决定》)A,充分体现了以习近平同志为核心的党中央对中国特色社会主义建设规律认识的深化,对科学社会主义理论与实践的丰富发展,为成功实现“中国之治”提供了深厚的制度基础和有力的制度保障。  相似文献   
2.
黄铜器表面着色方法的研究   总被引:3,自引:0,他引:3  
在总结古代铜器表面处理的文献基础上一通过化学成膜探讨含锌32%-36%的黄铜试样表面着色的方法,通过调整和控制试液的浓度、温度、酸度及浸泡时间的实验,确定黄铜表面栗色膜形成的最佳条件。对表面形成的粟色膜用多种实验手段进行了测定,结果表明栗色股厚度约为8μm主要组成为Cu2O。并对化学过程中形色栗色膜的机理作了初步探体  相似文献   
3.
明墓出土的历书,粘连固结成块,脆硬易于折断。通过实验分析研究,探明其主要原因可能是木质素选择性地吸附的钙铁离子与蛋白质的分解物形成复杂物质,沉积在纸上,渗入书内所致。故揭取该历书的关键是去除钙离子,EDTA二钢,碱性过氧化氢、气相二氧化硅等的分步处理,使脆硬的纸张软化,再逐页分离揭取,然后再去除色素沉淀物,终于恢复了书的原貌。  相似文献   
4.
A human skull, buried about 2500 years ago in a Bronze Age cemetery at Jinggouzi, a site of an important ethnic group in ancient China, appeared to have characteristics of fibrous dysplasia. The CT images indicated a reduction in bone density and relatively homogeneous lesions. More features were revealed using CT reconstruction techniques. Lesions seen in low‐magnification images using a 3D deep‐field microscope had an irregular honeycomb‐like structure. At higher magnification, the trabeculae morphology and the gaps between the trabeculae were irregular and varied in size and shape. Paraffin‐embedded specimens stained with HE showed trabeculae with tortuous irregular arrangements varying in shape and width. The irregular trabeculae of woven bone has been described as having fibrous dysplasia. Molecular analysis of the GNAS gene indicated no mutation. This provides a non‐invasive approach for us to make more comprehensive diagnoses and to assist research into ancient human diseases.  相似文献   
5.
位于四川省阆中市的大像山石窟,主要开凿于中晚唐和宋代,明清时期也有少量开凿。现有37龛,以方形龛、外方内圆拱形龛及圆拱形龛为主,方形龛最为多见。龛楣大多无装饰,雕刻简单。题材主要有弥勒佛、七佛、千佛、观音、天王、力士、经幢及舍利塔等。造像组合较少,以单身造像为多。阆中独特的地理位置,使得大像山石窟兼具广元、巴中两地石窟的特点,其丰富的内容为巴蜀佛教石窟寺的深入研究提供了重要的实物资料。  相似文献   
6.
The concept of providing a fuse in a structural system has been both developed and investigated over the past few years (e.g., the use of replaceable links in eccentrically braced frames or the use of replaceable links in the new San Francisco-Oakland Bay Bridge). This paper presents a new coupling beam with a creative fuse installed in the mid-span of a steel-concrete composite beam via an end plate and high-strength bolts. First, a practical design methodology of a replaceable coupling beam is presented. Next, the seismic behavior of the proposed fuse is tested and evaluated, and two structural wall specimens with or without a fuse are designed and fabricated according to the proposed design methods. The two specimens possess similar shear capacities under large-scale cyclic loading, and the walls of the two specimens show similar failure modes; however, the new walls exhibit slightly lower levels of damage than the conventional walls. In particular, the inelastic deformation and damage of replaceable coupling beams are mainly concentrated in the fuse, whereas the non-yield segment and the beam-wall pier interfaces remain nearly intact and produce only slight damage, which is beneficial regarding the replacement of the fuse in post-earthquake events.  相似文献   
7.
正It is just the dawn,but the sheepfolds have already begun to move restlessly.Sunlight makes its way in.Tashi Tsedan and Redan open the sheepfolds one after another.Flocks of sheep suddenly gush out like an influx of water from an opened gate.These two herdsmen from Jirong Village in Drik Town of Gampa County are fulfilling their duty grazing these flocks of Gampa sheep,a well-known breed of Tibetan sheep.  相似文献   
8.
9.
洪武年间,湖广各府级中心城治、西南少数民族等"寇乱"为患地区率皆设立卫所、筑城守御,并辅以巡检司、土司等多重防御力量。在其障护之下,腹里州县安全无虞,实无修固城防之必要。自洪武朝以至宣德朝,湖广地区修筑、维护城池主要限于驻军各地,对于其他众多普通州县并未从严要求,各地不修城的情形相当普遍。正是洪武朝奠定的颇为严密的区域安全防御体系保障了地方安定,为明前期实行这种相对宽松的筑城政策创造了条件。一些学者所谓明代"一贯积极、严厉的"筑城政策似乎并不完全切合明前期的实际。  相似文献   
10.
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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