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11.
The acidic volatile decomposition products (VDP) produced by a hydrogenated cottonseed oil maintained at 185C with periodic frying of moist cotton balls and with periodic additon of fresh fat to replenish the fat lost due to evaporation, decomposition, and adsorption by the cotton balls were collected, fractionated and characterized. A total of 38 acidic compounds were identified. They consisted of 13 saturated acids, 11 unsaturated acids, five aldehydo acids, two hydroxy acids, two keto acids, and five dicarboxylic acids. The similarities and differences between the acidic VDP produced by a more unsaturated corn oil and a more saturated hydrogenated cottonseed oil under simulated commerical deep fat frying conditions are discussed. Paper of the Journal Series, New Jersey Agricultural Experiment Station, Rutgers, The State University.  相似文献   
12.
As a preliminary treatment in the PVC-electroplating procedure, treatment with dimethylformamide followed by sensitization leads to a finely roughened and a highly hydrophilic surface with reducing power. This is caused by the formation of an ionic complex compound between dimethylformamide and tin(II) chloride absorbed in the PVC surface. A much more finely and deeply etched surface which exhibits higher adhesion through the mechanical interlocking effect is obtained with the PVC blends containing the plasticizer with a low value of interaction parameter and with a solubility parameter approximate to that of PVC. Adhesion of the metal layer to the PVC surface thus obtained is improved about 1.5 times by thermal aging at 120°C for 20 min.  相似文献   
13.
Kosaku Tamura  Toshio Masuda 《Polymer》2008,49(21):4494-4501
Novel acetylene monomers substituted with phenylethynylcarbazolyl groups, 3-[(4-octylphenyl)ethynyl]-9-propargylcarbazole (1), 3,6-bis[(4-octylphenyl)ethynyl]-9-propargylcarbazole (2), 9-(4-ethynylphenyl)-3-[(4-octylphenyl)ethynyl]carbazole (3), and 9-(4-ethynylphenyl)-3,6-bis[(4-octylphenyl)ethynyl]carbazole (4) were synthesized, and polymerized with Rh+(nbd)[η6-C6H5B(C6H5)3] and WCl6-n-Bu4Sn catalysts. The corresponding polyacetylenes with number-average molecular weights ranging from 9200 to 94?000 were obtained in 20-98% yields. The IR spectra of the polymers revealed that acetylene polymerization took place at the terminal ethynyl group, while the ethynylene group remained intact. The UV-vis absorption band edge wavelengths of W-based poly(3) and poly(4) were longer than those of the other polymers. W-Based poly(4) emitted fluorescence with the highest quantum yield (41%). Poly(1) exhibited excimer-based fluorescence in dilute solution.  相似文献   
14.
A new finishing process for metal molds by large-area electron beam (EB) irradiation is proposed in this study. In the large-area EB irradiation equipment used here, an EB with high-energy density is irradiated without focusing the beam, and so the EB with a maximum diameter of 60 mm can be used for melting or evaporating metal surface instantly. Experimental results show that the surface roughness decreases from 6 μmRz to less than 1 μmRz in just a few minutes under proper machining conditions. The corrosion resistance of metal mold surface also could be greatly improved by large-area EB irradiation. Furthermore, the surface roughness of tilting surface close to 90° could be well improved. Therefore, large-area EB irradiation method has a possibility to become a high-efficiency finishing process for metal molds.  相似文献   
15.
Sato F  Okui H  Akiba U  Suga K  Fujihira M 《Ultramicroscopy》2003,97(1-4):303-314
Origins of peak broadening in a histogram of measured adhesive forces were studied. The adhesive forces were measured in water by pulsed-force-mode atomic force microscopy. One sample was prepared by a microcontact printing method on a sputtered gold film with fine grains, on which CH(3)- and COOH-terminated regions were produced. Gold surfaces of other samples were chemically modified homogeneously by a self-assembling method in solution. Their surfaces were, however, topographically different, i.e. (i) an Au(111)-terrace-rich gold film prepared by vacuum vapor deposition at high temperature and (ii) sputtered gold films on cover glass with different grain sizes obtained by different deposition time. These sample surfaces and the probe tip surface were all CH(3)-terminated by self-assembled monolayers with CH(3)(CH(2))(19)SH. The main origin of peak broadening in the histogram was the topographic effect. Namely, the change in the grain sizes and the change in multiplicity of contacts between the tip and convexities of the grains resulted in the distribution of the observed adhesive forces.  相似文献   
16.
Endothelial dysfunction is often found in both hyperuricemia and hemodialysis patients. Recent studies have shown that treating hyperuricemia with allopurinol improves endothelial dysfunction. This study is performed to assess the effect of febuxostat on endothelial dysfunction in hemodialysis patients with hyperuricemia. We randomly assigned 53 hemodialysis patients with hyperuricemia to a febuxostat (10 mg daily) group and a control group and measured flow‐mediated dilation, serum uric acid (UA) levels, systolic and diastolic blood pressure, malondialdehyde‐modified low‐density lipoprotein (MDA‐LDL), and highly sensitive C‐reactive protein (hsCRP) at baseline and at the end of a 4‐week study period. Flow‐mediated dilation increased from 5.3% ± 2.4% to 8.9% ± 3.6% in the febuxostat group but did not change significantly in the control group. Treatment with febuxostat resulted in a significant decrease in serum UA level and a significant decrease in MDA‐LDL compared with baseline, but no significant difference was observed in hsCRP level or blood pressure. No significant differences were observed in the control group. Febuxostat improved endothelial dysfunction and reduced serum UA levels and oxidative stress in hemodialysis patients with hyperuricemia.  相似文献   
17.
We examined the effect of matrix metalloproteinase (MMP) inhibitor (CS-610) on experimental pseudomonal corneal ulceration by clinical and histological evaluation. Intrastromal injection of 3.5 microliters sterile culture broth of P. aeruginosa, IID-1117 (13.5 unit Type I collagenase equivalent proteinase activities), was done to induce corneal ulcers in guinea pigs. The animals were divided into two groups of 23 each. The CS-610 group received topical CS-610 (400 micrograms/ml) treatment at 2-hour intervals and the control group received only the vehicle of CS-610 at the same intervals. In the control group, corneas developed acute corneal damage following corneal ulcerations at 6-12 hours. In the CS-610 group, these corneal lesions were inhibited in most of the eyes (p < 0.01). In the late period, as inflammatory cells migrated into the cornea, some animals of the CS-610 group developed corneal ulcer. The results indicated that CS-610 had a potent inhibitory activity against pseudomonal proteinases in vivo. The results also suggested that the mechanism of the ulceration model involved not only pseudomonal proteinases but also endogenous responses.  相似文献   
18.
Symbolic numeric algorithms for polynomials are very important, especially for practical computations since we have to operate with empirical polynomials having numerical errors on their coefficients. Recently, for those polynomials, a number of algorithms have been introduced, such as approximate univariate GCD and approximate multivariate factorization for example. However, for polynomials over integers having coefficients rounded from empirical data, changing their coefficients over reals does not remain them in the polynomial ring over integers; hence we need several approximate operations over integers. In this paper, we discuss computing a polynomial GCD of univariate or multivariate polynomials over integers approximately. Here, “approximately” means that we compute a polynomial GCD over integers by changing their coefficients slightly over integers so that the input polynomials still remain over integers.  相似文献   
19.
To confirm the theory for gas absorption accompanied by an instantaneous irreversible reaction in laminar falling films of power-law liquids which was presented in a previous paper, experiments were carried out on the absorption of pure carbon dioxide into aqueous kaolin slurries containing sodium hydroxide by using a long wetted-wall column. The experimental data were in fairly good agreement with the theoretical predictions, the average deviation being 3.0%. The discussion on the effect of the power-law index of the liquid upon the reaction factor suggested an approximate method of estimating the reaction factors for power-law liquids.  相似文献   
20.
We have theoretically examined whether magnetic moment of iron atom can be induced or not when highly electronegative elements such as halogen or oxygen atoms are doped. Based on the impurity Anderson model, we evaluated the green function of d electrons. Through the analysis of green function, it is disclosed that a magnetic moment can be induced by impurity potential caused from doping elements, although intrinsic β-FeSi2 is non-magnetic. In particular, high electronegativity of doping atoms and/or strong Coulomb repulsive interaction between conduction electrons and doped atoms easily induce magnetic moment from non-magnetic state. In the viewpoint of chemical bonding, such an induced magnetic moment appears as a result of decomposition of covalent FeSi bonds by a strong electronegative impurity potential, because the broken bonds create the unpaired 3d electrons.  相似文献   
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