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排序方式: 共有307条查询结果,搜索用时 15 毫秒
51.
Shioda H Satoh K Nagai F Okubo T Seto T Hamano T Kamimura H Kano I 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2003,44(4):203-207
Juice and integument of leaves of 3 Aloe species, Aloe vera, A. ferox and A. africana, are not allowed to be used as food according to the Pharmaceutical Affairs Law in Japan. On the other hand, whole leaves of A. arborescens can be used as food. The present study was designed to distinguish Aloe species by random amplified polymorphic DNA (RAPD) analysis. DNA was isolated from fresh and dried leaves of the 4 Aloe species. Five out of 32 different 10-mer primers examined were useful for analysis. By comparison of the characteristic bands of PCR products on agarose gel, it was possible to distinguish the 4 species. Thus, the botanical species of Aloe in commercial food products can be identified by RAPD analysis. 相似文献
52.
Shirouchi B Kawamura S Matsuoka R Baba S Nagata K Shiratake S Tomoyori H Imaizumi K Sato M 《Lipids》2011,46(8):789-793
Guar gum has a well-recognized hypolipidemic effect. This effect is thought to be due to the physicochemical properties of
guar gum, which may cause changes in adsorption of lipids or the viscosity of the intestinal contents. Guar gum is a non-specific
absorption inhibitor of any type of lipid-soluble compound. Permanent lymph duct cannulation was performed on rats to investigate
the effects of dietary guar gum on lymph flow and lipid transport. Rats fed a 5% guar gum diet were compared with those fed
a 5% cellulose diet, and lymph was collected after feeding. The water-holding capacity (WHC), settling volume in water (SV),
and viscosity of guar gum were compared with those of cellulose. Rats fed with the guar gum diet had significantly lower lymph
flow and lymphatic lipid transport than did rats fed with the cellulose diet. The WHC, SV, and viscosity of guar gum were
significantly higher than those of cellulose. We propose that dietary guar gum reduces lymph flow and thereby diminishes lipid
transport by means of its physicochemical properties related to water behavior in the intestine. 相似文献
53.
Y. Hayakawa K. Hayakawa T. Kuwada K. Nogami T. Sakai Y. Takahashi 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2008,266(17):3758-3769
Advanced applications of parametric X-ray radiation (PXR) such as energy-dispersive X-ray absorption fine structure (DXAFS) analysis and phase-contrast imaging have been developed at the Laboratory for Electron Beam Research and Application (LEBRA) of Nihon University. To improve the electron beam quality and geometrical stability of the target crystal, the cooling-water system for the linac and the PXR target was replaced with a new one capable of more precise control. As a result, the reliability of the experimental data in PXR applications, especially in X-ray imaging, has improved. The effect of the electron beam focusing on the target crystal was also investigated. The results of X-ray imaging with a long propagation distance and measurement of the time-structure of the PXR intensity suggest that the correlation between the electron beam profile and the X-ray coherence is rather complicated. It is possible that incident electrons cause some deformation of the target crystal, becoming the dominant factor restricting the quality of intense PXR. 相似文献
54.
Male Sprague-Dawley rats were fed a cholesterol-free (Exp. 1) or cholesterol-supplemented (Exp. 2) diet containing 20% casein
(control group) or 15% defatted squid and 5% casein (defatted squid group), as protein, for 14 d. Serum and hepatic cholesterol
concentrations were lower in rats fed defatted squid than in those fed casein in both cholesterol-free (−20%, P<0.05 and −15%, P<0.05, respectively) and cholesterol-supplemented (−25%, P<0.05 and −15%, P<0.05, respectively) diets. Hepatic triglyceride concentration was lower in the defatted squid than in the control groups
in both cholesterol-free (−51%, P<0.05) and cholesterol-supplemented diets (−38%, P<0.01). The activities of cytosolic fatty acid synthase and the NADPH-generating enzymes, malic enzyme and glucose-6-phosphate
dehydrogenase, in the liver were lower in the defatted squid than in the control groups in both cholesterol-free (−21%, P<0.01, −33%, P<0.05, and −33%, P<0.01, respectively) and cholesterol-supplemented diets (−34%, P<0.05, −57%, P<0.05, and −67%, P<0.05, respectively). The activity of mitochondrial carnitine palmitoyltransferase in the liver was comparable between the
control and defatted squid groups. The activity of Mg2+-dependent phosphatidate phosphohydrolase in the liver cytosol was lower in the defatted squid (−9%, P<0.05) than in the control groups only in the cholesterol-free diet. Fecal excretion of total steroids was stimulated by the
feeding of defatted squid in both cholesterol-free (+77%, P<0.005) and cholesterol-supplemented diets (+29%, P<0.01). These results suggest that the nonlipid fraction of squid exerts a hypocholesterolemic effect by increasing the excretion
of total steroids in feces. The fraction also induces a triglyceride-lowering activity in the liver by decreasing hepatic
lipogenesis. 相似文献
55.
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57.
Decomposition of Ruthenium Oxides in Lead Borosilicate Glass 总被引:2,自引:0,他引:2
Behaviors of apparent phase changes of Ru-containing oxides in lead borosilicate glass at high temperature have been investigated using X-ray diffraction and transmission electron microscopy in application to thick-film resistors. During firing of thick films containing Ru oxide powder and lead borosilicate glass frits, apparent phase changes of Ru oxides have been found to occur both ways between ruthenium dioxide and lead ruthenate pyrochlore via decomposition of one phase in glass and subsequent formation of the other. The formation of pyrochlore occurs in a lead-rich form, Pb2 (Ru2− x Pb x )O6.5 , whereas the formation of RuO2 is characterized by a platelike morphology instead of initial globular morphology. A general tendency is observed that RuO2 is stable in low-PbO glass compositions and at high temperatures, while Pb2 (Ru2− x Pb x )O6.5 is stable in high-PbO glass compositions and at low temperatures, with the implication that the stability of these phases is dictated by the chemical activity of PbO in the glass melt. 相似文献
58.
The tumor-promoting agent 4β-phorbol-12-myristate-13-acetate (TPA) is shown to be a potent stimulator of fatty acid synthesis
in isolated rat hepatocytes. The maximal effect of TPA is seen at 10−6 M, and the concentration for half-maximal effect is ca. 10−8 M. Stimulation of fatty acid synthesis by TPA is shown not to require the presence of extracellular Ca++. TPA produces a significant increase in lactate and pyruvate accumulation. The possible involvement of protein kinase C in
short-term regulation of fatty acid synthesis in the liver is discussed. 相似文献
59.
Thiobarbituric acid reaction of aldehydes and oxidized lipids in glacial acetic acid 总被引:1,自引:0,他引:1
Thiobarbituric acid (TBA) reaction of several aldehydes and oxidized lipids in glacial acetic acid was performed. All the
samples were freely soluble in the solvent used. Saturated aldehydes produced a stable yellow pigment with an absorption maximum
at 455 nm, a red pigment derived from malonaldehyde at 532 nm, and an orange pigment due to dienals at 495 nm. The absorbance
maximum was 7–9 per μmol for saturated aldehydes, 27.5 per μmol for malonaldehyde and about 2 per μmol for dienals. Autoxidation
of unoxidized lipids increased progressively in glacial acetic acid. When the TBA test was performed under nitrogen, autoxidation
of unoxidized lipids was inhibited completely. While saturated aldehydes produced no yellow pigment under nitrogen, oxidized
lipids produced a considerable amount of stable yellow pigment. The value for absorbance at 455 nm as a function of autoxidation
time paralleled those of peroxide values. The absorbance of most oxidized lipids at 455 nm was higher than at 532 nm. Yellow
pigment formation in the TBA test under nitrogen could not be ascribed to free saturated aldehydes but rather to unspecified
closely related substances. The stable yellow pigment was found to be an excellent indicator of lipid oxidation. 相似文献
60.
Yingxi Zhu Hiroko Ohtani Michael L. Greenfield Marina Ruths Steve Granick 《Tribology Letters》2003,15(2):127-134
The molecular-level function of model and commercial friction modifier additives in lubricants of the type used at the wet clutch interface in automatic transmissions has been studied using a surface forces apparatus (SFA) modified for oscillatory shear. The nanorheological properties of tetradecane with and without a model friction modifier additive (1-hexadecylamine) were examined in the boundary lubrication regime and compared to a fully-formulated automatic transmission fluid (ATF). 1-Hexadecylamine adsorbed as a single layer on the sliding surfaces, reduced the static frictional force and the limiting shear stress, and eliminated the stick–slip transition that exists in pure tetradecane. The ATF, which contains commercial-grade friction modifiers, showed nanorheological properties similar to those observed for tetradecane containing 0.1–0.2 wt% 1-hexadecylamine. 相似文献