全文获取类型
收费全文 | 109篇 |
免费 | 4篇 |
专业分类
化学工业 | 24篇 |
金属工艺 | 1篇 |
机械仪表 | 1篇 |
建筑科学 | 2篇 |
轻工业 | 13篇 |
无线电 | 3篇 |
一般工业技术 | 19篇 |
冶金工业 | 42篇 |
原子能技术 | 1篇 |
自动化技术 | 7篇 |
出版年
2022年 | 1篇 |
2021年 | 1篇 |
2020年 | 2篇 |
2019年 | 1篇 |
2018年 | 1篇 |
2017年 | 2篇 |
2016年 | 1篇 |
2015年 | 2篇 |
2014年 | 6篇 |
2013年 | 4篇 |
2012年 | 2篇 |
2011年 | 2篇 |
2010年 | 1篇 |
2007年 | 2篇 |
2006年 | 1篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 7篇 |
1997年 | 3篇 |
1996年 | 8篇 |
1995年 | 3篇 |
1994年 | 6篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 5篇 |
1990年 | 2篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1910年 | 2篇 |
排序方式: 共有113条查询结果,搜索用时 15 毫秒
1.
Summary Recent progress in the modelling of exchanged Cu sites and their interactions with small molecules, based on DFT cluster calculations, is briefly reviewed. 相似文献
2.
The lens epithelium of the human eye plays a crucial role in the pathogenesis of primary and secondary cataract. Sixty hematoxylin-eosinstained lens epithelia were examined using a light microscope. Cell parameters were compared to one another in the various age groups of patients, between patients with secondary cataract (radiation cataract, steroid cataract and traumatic cataract) and patients with senile cataract, and between male and female patients. The t-test was used for statistical comparison. The median cell density was 3116.5 cells/mm2. The median nucleus-plasma ratio was 1:2.74. Patients with secondary cataract had a larger medium cell and nucleus area as well as a higher nucleus-plasma ratio and a lower cell density than patients with senile cataract. A part from degenerative and proliferative cell changes we found various cell types. The age of patients and the cause of cataract correlate with morphometric changes of lens epithelium cells. However, there was no correlation between specific cytologic changes and causes of cataract. 相似文献
3.
4.
Beerens H Hass Brac de la Perriere B Gavini F 《International journal of food microbiology》2000,54(3):163-169
Fifty-eight samples of raw milk from three different farms were examined for the presence of bifidobacteria. Isolates were identified and compared with bifidobacteria isolated from dung of the cows that provided the milk. Of the raw milk samples, 88% harboured Bifidobacterium pseudolongum subsp. globosum, as did 95% of the dung samples. 相似文献
5.
O Ladefoged HR Lam G Ostergaard EV Hansen U Hass SP Lund L Simonsen 《Canadian Metallurgical Quarterly》1998,19(4-5):721-737
Male Wistar rats were dosed with 0, 1250, 3750 or 5000 mg/l of phenylglyoxylic acid (PGA) (CAS no. 611-73-4) in the drinking water ad libitum for 3 months. During the entire treatment period, there were no gross signs of toxicity related to PGA. No changes in neurobehavior were found after using a functional observational battery or radial arm maze. An increased relative kidney weight was seen in the highest dose-group (Controls: 0.504 +/- 0.031 g/100 g b.wt.; 5000 mg PGA/l: 0.579 +/- 0.033 g/100 g b.wt.; p<0.01). No other organ weights were affected. Histopathology revealed no change in kidney structure. No changes in clinical biochemistry. In the highest dose-group three animals out of ten showed reduction in peripheral nerve myelin sheath thickness. No such changes were seen in the control group. The study revealed no changes in auditory brain stem response but minor changes in electroretinography. The noradrenaline (NA) concentration decreased in pons and thalamus whereas it increased in medulla oblongata and whole brain. The dopamine (DA) concentration increased in cerebellum, hippocampus, pons, and whole brain. The most marked DA increase was seen in hippocampus (Controls: 0.56 +/- 0.10 nmol/g tissue; 5000 mg/l: 1.04 +/- 0.11 nmol/g tissue; p<0.001). The 5-hydroxytryptamine (5-HT) concentration decreased in cerebellum, cerebral cortex, hippocampus, and medulla oblongata, whereas it increased in thalamus. The yield of synaptosomal protein, synaptosomal NA, DA, and 5-HT concentrations, and DA uptake rate were not affected. When dosed males were mated with naive females, there were no differences between groups in the pregnancy rate, number of corpora luteae, implantations, live or dead fetuses, resorptions, preimplantation loss, or postimplantation loss. It is concluded that a part of the effects on kidney, peripheral nerves, and vision, which have previously been reported after exposure to styrene, might be induced by the styrene metabolite, PGA. If PGA has ototoxic effects in rats, the dosing in the present study is not sufficient to induce the necessary ototoxic concentration in blood. Alternatively, the ototoxicity of styrene, like toluene, may be caused the parent compound itself and not by a metabolite like PGA. 相似文献
6.
Henning Buddenbaum Oksana Stern Barbara Paschmionka Erik Hass Thomas Gattung Johannes Stoffels 《International journal of remote sensing》2013,34(18):4590-4605
Drought stress is expected to become a recurrent problem for central European forests due to regional climate change. In order to study the effects on one of the most common tree species in Germany, the European beech (Fagus sylvatica), young potted beech trees were exposed to drought stress in a controlled experiment and their reaction was observed using visible/near-infrared (VNIR) and shortwave infrared (SWIR) field imaging spectroscopy cameras mounted on a platform. Equivalent water thickness (EWT) and leaf chlorophyll content (LCC) were measured and partial least squares (PLS) regression models were trained using these reference measurements and reflectance spectra of the trees. The models were applied to create maps of these properties with a spatial resolution in the millimetre range. These maps can be used to study the spatial distribution of EWT and LCC for single leaves or even for intra-leaf variability. Both properties can be estimated using only the VNIR sensor, but EWT estimation improves considerably by also incorporating SWIR data. LCC estimations with SWIR data alone do not work satisfactorily. 相似文献
7.
8.
G. P. Casey C. A. Hass D. W. Hysert W. M. Ingledew 《Journal of the Institute of Brewing》1983,89(6):393-396
A yeast shipment method suitable (depending on vessel size) for 1 to 20 litres of slurried yeast is described. The method was investigated primarily assuming transit (storage) temperature at approximately 21°C. Under these conditions, the contained yeast was stable over 116 h at temperatures well under 16°C, and maintained its viability, fermentability and vigour to reinitiate new fermentations. Under more vigorous climatic conditions, shipment time would have to be reduced, but adequate protection time was afforded for all but the most extreme sub-zero situations. 相似文献
9.
Continuous fiber reinforced ceramic matrix composites (CMC’s) made from aluminum oxide fibers and matrices are usually fabricated
using a tape casting process. In this process, ceramic slurry consisting of the oxide powder, a polymeric binder and a solvent
is infiltrated into a woven ceramic fiber mat. After evaporation of some of the solvent, the resulting flexible tapes can
be stacked and sintered to create a composite component. Because the fraction of ceramic powder in the slurry can vary during
processing, in-situ compositional sensors are required for on-line feedback control to limit property variations in the composite
material. Since the dielectric properties of the slurry components are distinctly different, the effective permittivity of
the slurry depends upon its composition. Here, a non-contact capacitance probe has been used to explore the possibility of
capacitance sensing for compositional control. Results indicate that the removal of solvent during a precision drying step
may be monitored by this approach. The feasibility of monitoring changes in the slurry’s composition during infiltration of
the fiber mat is also discussed. 相似文献
10.