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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.
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   
3.
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   
4.
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   
5.
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   
6.
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   
7.
本文以广州荔枝湾涌历史文化街区为例,运用扎根理论研究荔枝湾涌1940年代以来地方发展变迁与居民地方感的关系,进而挖掘居民地方感变化机制。研究发现:荔枝湾涌居民的地方感主要受生态环境、建筑与配套服务、集体记忆、活动类型、人际关系等因素的影响,其中生态环境起主导性作用;积极地方感主要来源于集体记忆的保留与延续;消极地方感主要来源于破旧的居住环境及落后的配套服务;此外,文章提出内向型地方感和外向型地方感的概念,认为随着城市发展,在地方发展变迁过程中,地方感由内向型地方感转变为内向型和外向型相结合的地方感。两种地方感相互作用,互相调节,更有利于地方稳定、开放、包容地发展。  相似文献   
8.
The provenance of more than 2200-year-old terracotta warriors and horses in the Qin Shihuang Mausoleum is still a mystery, even though some researchers have inferred that the terracotta figures were produced near the mausoleum. The sporomorphs (pollen and spores) extracted from terracotta fragments of a warrior and a horse and compared with those obtained from soil samples from the Qin Dynasty layer in Pit No. 2 of the Qin Shihuang Mausoleum indicate that the pollen spectrum from the terracotta horse is different from that of the warrior, but similar to the local soil samples. Herbaceous pollen was dominant in the warrior sample, while arboreal pollen predominates in the horse and soil samples. Palynological evidence suggests that the terracotta horses were produced at a locality near the mausoleum, while the warrior came from a site which was further afield.  相似文献   
9.
本文根据文献与考古资料,认为辽越国公主槊古公主以从嫁户所建的头下城懿州即今辽宁阜新塔营子古城.改为行政州以后,懿州下辖宁昌、顺安两县,顺安就是塔营子古城,宁昌即塔营子北10公里的平安地古城.辽代末年,将懿州州治从顺安迁到了宁昌.金皇统三年(1143年)又将宁昌省入顺安,州治也迁回了顺安,此后至元代,没有变化,懿州州治一直在塔营子古城.  相似文献   
10.
河西地区地域辽阔,土地广袤,我们的祖先从远古时期就开始开发这片土地,两汉时期,开发活动达到了一次高潮.汉代对西北的开发主要采取徙民实边和戍守屯田两种措施.我们力图从史书和汉简中找到一些原始材料,管窥当年开发西北的真实状况,为今天开发西北的活动提供一些经验及借鉴.  相似文献   
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