全文获取类型
收费全文 | 832篇 |
免费 | 30篇 |
国内免费 | 9篇 |
专业分类
电工技术 | 56篇 |
综合类 | 5篇 |
化学工业 | 258篇 |
金属工艺 | 16篇 |
机械仪表 | 11篇 |
建筑科学 | 34篇 |
矿业工程 | 1篇 |
能源动力 | 14篇 |
轻工业 | 70篇 |
水利工程 | 1篇 |
石油天然气 | 3篇 |
无线电 | 66篇 |
一般工业技术 | 157篇 |
冶金工业 | 73篇 |
原子能技术 | 24篇 |
自动化技术 | 82篇 |
出版年
2022年 | 8篇 |
2021年 | 13篇 |
2020年 | 4篇 |
2019年 | 15篇 |
2018年 | 9篇 |
2017年 | 11篇 |
2016年 | 16篇 |
2015年 | 14篇 |
2014年 | 22篇 |
2013年 | 31篇 |
2012年 | 27篇 |
2011年 | 38篇 |
2010年 | 26篇 |
2009年 | 39篇 |
2008年 | 43篇 |
2007年 | 29篇 |
2006年 | 47篇 |
2005年 | 35篇 |
2004年 | 37篇 |
2003年 | 31篇 |
2002年 | 25篇 |
2001年 | 17篇 |
2000年 | 13篇 |
1999年 | 19篇 |
1998年 | 42篇 |
1997年 | 26篇 |
1996年 | 15篇 |
1995年 | 15篇 |
1994年 | 14篇 |
1993年 | 13篇 |
1992年 | 4篇 |
1991年 | 10篇 |
1990年 | 9篇 |
1989年 | 9篇 |
1988年 | 11篇 |
1987年 | 11篇 |
1986年 | 18篇 |
1985年 | 8篇 |
1984年 | 9篇 |
1983年 | 12篇 |
1982年 | 13篇 |
1981年 | 6篇 |
1980年 | 11篇 |
1979年 | 11篇 |
1978年 | 6篇 |
1977年 | 5篇 |
1976年 | 4篇 |
1975年 | 3篇 |
1973年 | 4篇 |
1972年 | 3篇 |
排序方式: 共有871条查询结果,搜索用时 15 毫秒
71.
Takuya Kitabatake Tetsuo Uchikoshi Fumio Munakata Yoshio Sakka Naoto Hirosaki 《Journal of the European Ceramic Society》2012,32(7):1365-1369
The compaction of a Eu-doped Ca-α-SiAlON phosphor powder was performed by electrophoretic deposition (EPD). The effect on the adhesion and optical properties of the silica precursor as both a binder of the powder and a filler of the air voids were evaluated. The adhesion of the silica impregnated composite film to the silica glass substrate was characterized by the tape test. The improvement of the external quantum efficiency was confirmed from the PL spectra measurement after the silica impregnation. The temperature dependence of the external quantum efficiency was also investigated in order to discuss the advantage of using the silica precursor as a binder for high-brightness LED applications. 相似文献
72.
Ronaldo Fumio Hashimoto Junior Barrera 《Journal of Mathematical Imaging and Vision》2001,15(3):197-216
W-operators are discrete set operators that are both translation invariant and locally defined within a finite window W. A particularly interesting property of W-operators is that they have a sup-decomposition in terms of a family sup-generating operators, that are parameterized by the operator basis. The sup-decomposition has a parallel structure that usually is not efficient for computation in conventional sequential machines. In this paper, we formalize the problem of transforming sup-decompositions into purely sequential decompositions (when they exist). The techniques were developed for general W-operators, specialized for increasing W-operators and applied on operators built by compositions of dilations and erosions. 相似文献
73.
74.
K Tanaka K Iyama M Kitaoka Y Ninomiya T Oohashi Y Sado T Ono 《Canadian Metallurgical Quarterly》1997,29(7):563-570
Type IV collagen, the major component of basement membrane, consists primarily of alpha 1(IV) and alpha 2(IV) chains. Recently, other types of collagen IV chains, i.e. alpha 3(IV), alpha 4(IV), alpha 5(IV) and alpha 6(IV) chains, have been identified by protein chemistry and molecular cloning. We have examined the diversity of the assembly of alpha (IV) chains of the basement membrane surrounding tumour nests of basal cell carcinomas, in tissues from 11 patients, by immunohistochemical analysis using specific monoclonal antibodies to six alpha (IV) chain. The immunostaining profile of each chain differed with respect to the histological subtypes of basal cell carcinoma. In the morphea-like subtype, which was more invasive, alpha 1(IV) and alpha 2(IV) chains were discontinuously stained, and alpha 5(IV) and alpha 6(IV) chains were entirely absent. However, in the superficial subtype, which was non-aggressive, alpha 1(IV), alpha 2(IV), alpha 5(IV) and alpha 6(IV) chains were well stained compared with the other subtypes of basal cell carcinoma. In addition, in the solid subtype, which showed slow growth and ulceration, alpha 1(IV) and alpha 2(IV) chains were continuously stained, and alpha 5(IV) and alpha 6(IV) chains were discontinuous or absent. The assembly of alpha 5(IV) and alpha 6(IV) chains into the basement membrane was inhibited in the solid and morphea subtypes of BCC. This differential expression of type IV collagen chains seems to be associated with the invasive potential of basal cell carcinoma. 相似文献
75.
Yoshihisa Maruyama Fumio Yamazaki 《Journal of Wind Engineering & Industrial Aerodynamics》2006,94(4):191-205
In expanding expressway networks in Japan, various types of structures have been constructed, e.g., long span bridges and bridges with high piers. The expressway structures are well designed for the external dynamic forces, e.g., earthquakes and strong winds. However, for further safety promotion of the expressway networks, it is important to evaluate the drivers’ responses under strong dynamic disturbances. The present authors have investigated the moving stability of a vehicle under seismic motion based on both numerical simulation and virtual experiments using a driving simulator. Strong crosswind is considered as another factor that makes it difficult for drivers to control their vehicles. This study investigates the moving stability of a vehicle under strong crosswind based on numerical analyses and driving simulator experiments. To predict the future position of a moving vehicle including the reaction of a driver, the second-order predictable correction model is used in the numerical analyses. The results obtained from the numerical and experimental studies are compared and the validity of the driver model is discussed. It is expected that this research is helpful for the decision-making of expressway closure under strong wind and the design of wind barriers. 相似文献
76.
M Khaleduzzaman H Sumiyoshi Y Ueki K Inoguchi Y Ninomiya H Yoshioka 《Canadian Metallurgical Quarterly》1997,45(2):304-312
Type XIX collagen is a newly discovered member of the FACIT (fibril-associated collagens with interrupted triple helices) group of extracellular matrix proteins. Based on the primary structure, type XIX collagen is thought to act as a cross-bridge between fibrils and other extracellular matrix molecules. Here we describe the complete exon/intron organization of COL19A1 and show that it contains 51 exons, spanning more than 250 kb of genomic DNA. The comparison of exon structures of COL19A1 and other FACIT family genes revealed several similarities among these genes. The structure of exons encoding the noncollagenous (NC) 1-collagenous (COL) 1-NC 2-COL 2-NC 3-COL 3-NC 4 domain of the alpha1(XIX) chain is similar to that of the NC 1-COL 1-NC 2-COL 3-NC 3 domain of the alpha2(IX) chain except for the NC 3 domain of alpha1(XIX). The exons encoding the COL 5-NC 6 domain of alpha1(XIX) are also similar to those of the COL 3-NC 4 domain of alpha1(IX) chain. Previously, COL19A1 was mapped to human chromosome 6q12-q14, where COL9A1 is also located. Likewise, the present work shows that the mouse Col19a1 gene is located on mouse chromosome 1, region A3, where Col9a1 has also been mapped. Taken together, the data suggest that COL19A1 and COL9A1 (Col19a1 and Col9a1) were duplicated from the same ancestor gene of the FACIT family. Three CA repeat markers with high heterozygosity were found in COL19A1. These markers may be useful for linkage analysis of age-related inheritable diseases involved in eyes and/or brain. 相似文献
77.
We have attempted to synthesize the meixnerite (Mg–Al–OH) type layered double hydroxide (LDH) by a two step milling operation
of a mixture of Mg(OH)2 and Al(OH)3 with water. In the first-step, a mixture of the starting materials was milled for 1 h without water, and the product prepared
in the first-step was milled for 2 h with water in the second-step milling operation. The milled products were characterized
by X-ray diffraction (XRD), Fourier transform infrared (FTIR), and thermo gravimetric-differential thermal analyses with mass
spectroscopy (TG-DTA/MS). The surface morphology was characterized by scanning electron microscopy (SEM). Meixnerite with
a small amount of carbonate was successfully synthesized mechanochemically at ambient conditions by milling for only 3 h in
a planetary ball mill. 相似文献
78.
Processability of thermoplastic elastomer (TPE) prepared by radiation-induced grafting of methyl methacrylate (MMA) onto radiation vulcanized natural rubber latex (RVNRL) has been evaluated using a kneader and a hot roll mill at 150°C. It was found that mixing time and revolution rate (rpm) of the kneader have significantly affected the processability. The longer mixing time and the higher revolution rate result in better processability. In such processing conditions, however, the mechanical properties were found to be inferior because the molecular chain scissions occurred during the mixing. A considerable improvement of mechanical properties was obtained when the mixing was carried out without added process oils. Blends of the grafted vulcanized natural rubber latex (RVNRL-g-PMMA) and MMA grafted on unvulcanized natural rubber latex (NRL-g-PMMA) improved processability where the better processability could be achieved at a shorter mixing time and a lower revolution rate. In addition, a comparable value of mechanical properties was obtained. 相似文献
79.
Shigeaki Abe Yoshinori Nagoya Fumio Watari Hiroto Tachikawa 《Computational Materials Science》2011,50(9):2640-2643
The evaporation processes of water molecules adsorbed in the edge region of graphene have been investigated by means of direct MO–MD method. A large system composed of 29 water molecules and a graphene sheet (C96H24) was used as a model system. The edge carbon atom of graphene was terminated by hydrogen atom. The geometry optimization showed that the water molecules interact with the hydrogen atoms in the edge region of graphene. At low temperature (300 K), the water molecules were dissociated as water clusters from the graphene. On the other hand, in addition to the dissociation of water clusters, the isolated water molecule was also found as dissociation product at high temperature (500 K). The mechanism of water evaporation was discussed on the basis of theoretical results. 相似文献
80.
Shinoda N Hashimoto Y Takagi M Kojima F Onodera T Sugiura K 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2011,52(1):24-27
A method for confirming identification of prohibited species tissue in animal feed has been developed on the basis of PCR-RFLP analysis. In Japan, to prevent the spread of BSE through animal feed, the use of animal protein in feed has been regulated. Species-specific PCR detection of prohibited species materials in feed has been used as one of a series of laboratory tests to ensure the proper implementation of the feed regulations. However, since the result of this PCR method is determined only by amplicon length, it is sometimes necessary to confirm whether or not the positive result is due to the effect of a non-specific reaction. For this purpose, DNA sequencing is the best way to confirm the test result but it is not suitable for routine analysis because of the required time and cost. In this study, we developed an easy and rapid method to confirm the species identification (mammals, ruminants and cattle) by using 4 restriction enzymes: SmlI, MboI, BlnI and Hpy188III. This PCR-RFLP method, which ensures identification of prohibited animal species in feed, is useful for enhancing the reliability of feed inspection for BSE prevention. This method will be added to the Official Methods of Feed Analysis. 相似文献