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1.
In archaeology, strontium isotope analysis is developing into an efficient scientific technique for tracing the movement of prehistoric humans and animals. Determining the local bioavailable 87Sr/86Sr ratio range is the key to distinguishing whether the human or animal is indigenous to the local area. It has been shown that the 87Sr/86Sr ratio in the enamel of pigs can be an excellent sample to determine the range of local strontium isotope ratio at the site. However, pigs may not be all local at the site, and there is no special study on whether pigs’ different ages and tooth types impact the local strontium isotope characteristics. In this paper, the tooth enamel of 19 pigs from the Zaoshugounao site for strontium isotope ratio (87Sr/86Sr) by multicollector–inductively coupled plasma mass spectrometry. There were no significant differences in 87Sr/86Sr ratios of local pigs at different months and different molar types, which did not affect the determination of the local strontium isotope standard. Based on the local strontium isotope ratio range (0.711056–0.711476), we found that five pigs were non-local. The Jing and Wei river basins (in Guanzhong basin) and northern Shaanxi are likely sources of non-pigs.  相似文献   
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Pan, Z., Zhu, M., Zhu, Y. &; Jia, L., August 2017. A new antiarch placoderm from the Emsian (Early Devonian) of Wuding, Yunnan, China. Alcheringa 42, 10–21. ISSN 0311-5518.

Wufengshania magniforaminis, a new genus and species of the Euantiarcha (Placodermi: Antiarcha), is described from the late Emsian (Early Devonian) of Wuding, Yunnan, southwestern China. The referred specimens were three-dimensionally preserved in black shales, allowing a high-resolution computed tomography reconstruction of anatomical details. The new euantiarch is characterized by a large orbital fenestra, an arched exoskeletal band around the orbital fenestra and a developed obtected nuchal area of the skull roof. Maximum parsimony analysis, using a revised data-set of antiarchs with 44 taxa and 66 characters, resolves Wufengshania gen. nov. as a member of the Bothriolepididae, which is characterized by the presence of the infraorbital sensory canal diverging on the lateral plate, and the nuchal plate with orbital facets. New analysis supports a sister group relationship between Dianolepis and the Bothriolepididae. Luquanolepis, a coeval euantiarch from the neighboring site of the new form, is referred to the Asterolepidoidei and represents the basalmost and earliest member of the Asterolepidoidei.

Zhaohui Pan* [], Min Zhu* [], You’an Zhu? [] and Liantao Jia [] Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, PR China. *Also affiliated with University of Chinese Academy of Sciences, Beijing, 100049, PR China. ?Also affiliated with Uppsala University, PO Box 256, 751 05 Uppsala, Sweden.  相似文献   
4.
In Chinese traditional timber buildings, stitching is very common. When the bearing capacity or the rigidity is inadequate, a timber beam is often strengthened with another beam using the stitching method. The timber stitching beams are mainly of two types—the small-top/big-bottom type and the big-top/small-bottom type. To study the bending behavior of these two types of timber stitching beams, including the failure mode, the flexural capacity, the strain distribution at mid-span section, and the maximum deflection, bending tests are carried out on 14 timber stitching beams with Chinese traditional conformation for seven pine beams and seven fir beams. The results show that the failure modes of the small-top/big-bottom type of stitching beams all show brittle fractures at the bottoms of the bottom beams. The failure modes of the big-top/small-bottom type of stitching beams all show brittle fractures at the bottoms of the top beams. The distribution of section strain along the height of each part of the beam basically obeys plane hypothesis. Based on the theoretical and experimental analysis, the calculation formulas of flexural capacity and maximum deflection of these two types of timber stitching beams made of pine and fir are presented.  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   
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凌文超 《考古学报》2015,(2):187-228
<正>目次一绪言二"襍钱领出用馀见簿"的整理三襍钱"承馀新入簿"与"入受簿"的整理四库钱账簿体系与孙吴基层财政收支五结语一绪言近年来,湖南地区发掘清理了大批保存在古井中的简牍,包括三眼井楚简、里耶秦简、走马楼西汉简、东牌楼东汉简、五一广场东汉简、走马楼吴简、苏仙桥吴简和晋简以及兔子山战国至三国简牍。古井简牍遗存与边塞简和墓葬简不同,其发掘、整理和研究的模式不仅应借鉴边塞  相似文献   
7.
媒人现象的社会作用及其演变   总被引:1,自引:0,他引:1  
金陵 《东南文化》2007,(5):73-76
媒人是历史发展中的特殊民俗现象,也是一种特定的文化符号。媒人随一夫一妻制的聘娶婚的出现而出现,在防止男女乱性、保障婚姻安全、完善规范礼法等方面起着积极的历史作用。媒人不仅不会退出历史舞台,相反,在新的历史时期,媒人的社会作用将更加彰显。  相似文献   
8.
近代中国的领券制度   总被引:1,自引:1,他引:0  
银行业的领券制度,是近代中国货币发行史上一项独特的制度。笔者由于工作的关系,曾对领券制度产生的源流做了初步的梳理。然而,现存关于领券制度的资料比较缺乏,在这方面的研究有待深入。本文仅是提供一些基本情况,并谈点自己肤浅的看法。  相似文献   
9.
浙江平湖庄桥坟遗址出土的石犁是史前考古的新发现,属于痕迹文物。出土时木构件痕迹饱水,为暗褐色、开裂严重、整体呈腐蚀状,非常脆弱。针对器物的保存状况,因地制宜地制定一系列保护方法:木构件痕迹的脱水保护、底托的加固制作、木构件粘贴复原等,使文物得以长期保存。  相似文献   
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