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31.
为考察CuPCr型耐海水腐蚀钢不同显微组织的腐蚀行为,采用热轧后不同冷却方式分别获得贝氏体和铁素体+珠光体组织,进行模拟海水腐蚀的全浸加速腐蚀实验,并利用失重法测量腐蚀速率,采用SEM,XRD和电化学方法评价钢的腐蚀行为.结果表明:贝氏体组织能够在更短时间内形成比较致密的锈层,其耐蚀性能明显优于铁素体和珠光体组织.碳元素在贝氏体中的均匀分布减少了微电池数量,因而能够降低钢的腐蚀电流密度. 相似文献
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基于PLC的船舶电站物理仿真综合实验装置的监控设计 总被引:1,自引:0,他引:1
开发研制了船舶电站物理仿真实验装置,对其主要的工作原理,尤其是并车控制器设计部分进行简要地介绍.通过对分布式控制结构、底层数据采集和高端管理软件等方面的研究,提出利用WinCC6.0组态软件和西门子S7系列PLC对自动化电站物理仿真实验装置进行监控系统设计.仿真结果表明,系统可以正确地实时监测和记录,监测效果很好. 相似文献
34.
Tingting Yu 《Journal of Natural History》2015,49(9-10):509-526
Pseudelzalia longiseta gen. nov, sp. nov. and Paramonohystera sinica sp. nov. from subtidal sediment in the East China Sea are described. Pseudelzalia is characterized by 6 labial papillae and 10 cephalic setae, cylindrical buccal cavity, elongate (>2 anal body diameter) spicules, and conico-cylindrical tail devoid of terminal setae. It differs from Elzalia by the absence of terminal setae. Pseudelzalia longiseta sp. nov. is 647–853 μm long, has 7–8 μm long cervical setae, 11–14 μm long caudal setae, 25–41 μm long spicules about 2.1–2.7 anal diameter, and pointed tail-tip. Paramonohystera sinica possesses 12 cephalic setae, a character found in four congeners: Paramonohystera buetschlii (Bresslau and Schuurmans Stekhoven in Schuurmans Stekhoven, 1935, Paramonohystera pilosa Boucher, 1971, Paramonohystera concinna Lorenzen, 1977 and Paramonohystera halerba Fadeeva and Belogurov, 1987. It differs from P. buetschlii by shorter body (933–1023 μm versus 2000–2200 μm); from P. pilosa by the much shorter spicules (79–88 μm versus 167 μm) and narrower head (13–16 µm versus 32 µm); from P.concinna by smooth cephalic setae (versus segmented); and from P. halerba by the absence of two rows of setae on the ventral side of the tail (versus present). Based on the evaluation of nominal species, we recognize 14 valid species and provide an emended diagnosis and a tabular key for Paramonohystera.http://www.zoobank.org/urn:lsid:zoobank.org:pub:474B8F17-AED7-4078-8176-DFC499B78526 相似文献
35.
《Journal of Natural History》2012,46(23):2109-2123
Three new species of marine nematodes belonging to the genera Paranticoma (family Anticomidae) and Parodontophora (family Axonolaimidae) are described from the Bohai Sea and Yellow Sea. Paranticoma tricerviseta sp. nov. is similar to P. bandaenseMicoletzky and Kreis, in the spicules, but can be distinguished by the presence of a ventral projection on the spicules, three regularly arranged cervical setae in both the male and female, and two distinct ventral setae behind the anus. Parodontophora deltensis sp. nov. is close to P. paragranulifera (Timm, ) in the length of the amphids, with the ventral arm of the amphid extending past the base of the stoma, but can be separated by the ratio of dorsal arm length to ventral arm (0.36–0.55 versus 0.20–0.25) and the position of the excretory pore (at the middle level versus top level of the stoma), distinctive cervical setae arrangement and a longer renette cell. Parodontophora wuleidaowanensis sp. nov. is close to P. danker Belogurov and Kartavtseva, in the form of the amphids, but can be distinguished by the longer length of the ventral arm of the amphids and the distinctive arrangement of cervical setae. 相似文献
36.
《Journal of Natural History》2012,46(3-4):157-176
Collecting in southern Spain yielded five species of Parotoplana and one species of Parotoplanella (Proseriata: Otoplanidae). Four species of Paratoplana proved to be new to science. Parotoplana cucullata sp. n. is distinguished by the shape of the lateral spines in the copulatory organ and in the presence of a “glandular organ” around the distal portion of the female duct. Parotoplana fretigaditani sp. n. is similar to P. procerostyla Ax, 1956 in the general arrangement of spines, but their fine morphology is distinctive. Parotoplana varispinosa sp. n. differs from P. capitata Ax, 1956 in the shape and number of spines. Parotoplana mastigophora sp. n. has a unique morphology of the stylet, and the spines of the girdle markedly differ in size and shape. The karyotype of P. cucullata sp. n. (n = 6) is described. In addition, Parotoplana primitiva and Parotoplanella heterorhabditica, previously known from the Atlantic coast of France and north‐west Mediterranean, respectively, were found. The high proportion of new species demonstrates the present poor state of knowledge of interstial meiofauna. 相似文献
37.
《Journal of Natural History》2012,46(37-38):2391-2423
The present study raises the number of Ampelisca species recorded from the Brazilian coast from 18 to 21. The amphipod fauna of the Brazilian northeast coast is hardly known compared to that of the southeast coast. In this study, we describe three new species from the northeast coast: Ampelisca pseudobicarinata sp. nov., Ampelisca rocasensis sp. nov. and Ampelisca cristianae sp. nov, recorded previously as Ampelisca aff. lobata (Serejo et al. 2000). We also report a new record of Ampelisca burkei Barnard and Thomas, 1989. From the southeast coast a new species Ampelisca angraensis sp. nov. is described. An obscure species, Ampelisca soleata, which is very similar to Ampelisca brevisimulata, is herein redescribed and a neotype is designated. An updated key with all species of Ampelisca recorded from the Brazilian coast and comments on geographic distribution are given. 相似文献
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《Journal of Natural History》2012,46(2):407-414
Lernanthropus antofagastensis sp. nov., parasitic on Anisotremus scapularis, and inshore fish of Antofagasta, Chile, is described and illustrated. It resembles five other species of Lernanthropus in its dorsal plate and third leg, but can be distinguished from them by a combination of characters. L. trachuri Brian, 1903, is recorded, its male described and illustrated from specimens collected from Seriolella violacea and Trachurus murphy, taken in the same locality. 相似文献
40.
徐忠 《大连海事大学学报(自然科学版)》2009,(Z1)
机舱被誉为船舶的心脏,为船舶提供主要动力来源.优化机舱管理将对航运效率和安全提供有效保障.结合机舱管理实际,讨论如何运用第四代管理系统的理论进行轮机管理的优化. 相似文献