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21.
The determination of the kokumi peptide, γ-glutamyl-valyl-glycine (γ-Glu-Val-Gly) in raw scallop and processed scallop products was carried out using high pressure liquid chromatography–tandem mass spectrometry (LC/MS/MS). The detection of γ-Glu-Val-Gly was achieved using a multiple reaction monitoring (MRM) method. The optimised condition enabled the precise determination of γ-Glu-Val-Gly. Raw scallop contained 0.08 μg/g γ-Glu-Val-Gly, and the γ-Glu-Val-Gly levels in processed scallop products, such as dried-scallop and scallop extract, were measured to be 0.64 and 0.77 μg/g, respectively. This is the first report to confirm the existence of γ-Glu-Val-Gly in foodstuff.  相似文献   
22.
Somatic/embryonic stem cell cloning has made it possible to produce an individual genomically identical to another individual. However, the cloned animals have a variety of abnormalities caused by the aberrant gene modification, with insufficient reprogramming in cloning. We previously reported abnormalities in cloned mice at birth. In this study, we examined what abnormalities could be seen in cloned mice after long-term maintenance. The aged cloned mice showed multiple abnormalities: increase of body weight, some phenotypic abnormalities in the kidneys, testes and thymus, and lower urea nitrogen in their serum biochemical values. The kidneys of all cloned mice were hypertrophied, with a metamorphic or whitish appearance. The multiple lesions, including the enlarged renal pelvis and distension of the renal veins in histology, might be the result of urine accumulation by urinary tract obstruction. The testes of the cloned mice were atrophied, and showed no sperm formation in histology. In contrast, the thymus was rather hypertrophied, and a comparably increased number of lymphocytes were observed in the medulla, consisting mainly of T cells. By conducting a progeny test between the cloned mice, it was confirmed that these abnormalities in the aged cloned mice were not transmitted to their offspring, indicating that the incomplete reprogramming in clones might be in part responsible for the abnormalities detected in aged clones. These results indicate that the postnatal abnormalities observed in aged cloned mice are varied and can be restored through the germ line.  相似文献   
23.
Based on the previous success of adding ultra-fine carbon–PVA (polyvinyl alcohol) colloid solution to restore performance of weak batteries, a large scale test programme of practical batteries including those used in forklift, golf cart, taxi cab, truck and bus applications from 150 companies was carried out. More than 95% of the tested batteries exhibited excellent recovery in performance parameters including the specific gravity (S.G.), voltage and operation time (Ah capacity). The work reported here includes basic research studies to understand better the beneficial action of the carbon–PVA colloid additive.  相似文献   
24.
Racemic 3-methyl, 2-ethyl, 2-bromo, and 2-trimethylsilyl derivatives of formylferrocene were kinetically resolved by enantioselective reduction with a fermenting baker's yeast. Moreover, 2-methyl, 3-methyl, 2-ethyl, 2-bromo, and 2-trimethylsilyl derivatives of hydroxymethylferrocene were optically resolved with lipases by transesterification using vinyl esters.  相似文献   
25.
BACKGROUND: Finnish-type familial amyloidosis (FAP-IV) is an autosomal, dominantly inherited disorder characterized by progressive polyneuropathy and lattice corneal dystrophy type II. The vast majority of families with this disorder originated from Finland. Only two families, in neighboring districts, have been reported in Japan previously. METHODS: The authors report two additional Japanese patients with FAF-IV. The proband, a 70-year-old man, had decreased perspiration and abnormal facial muscle movement. Results of neurologic examination showed bilateral facial and hypoglossal nerve palsies, and an autonomic disturbance, including orthostatic hypotension and dysfunction of perspiration. Histochemical, immunohistological, and DNA studies confirmed the diagnosis of FAP-IV. RESULTS: Results of ophthalmologic examination showed asymptomatic lattice corneal dystrophy of both eyes, but the appearance of the cornea was different from that described in the patients from Finland. Lattice lines in the authors' patient were very fine, short, and glassy and could be observed with indirect retroillumination, but might be missed with direct illumination by the slit-lamp microscope. The proband's younger half-sister, a 68-year-old woman, showed clinical findings and laboratory data similar to those of the proband. CONCLUSION: The authors report two Japanese patients with lattice corneal dystrophy type II related to FAP-IV. This is the third Japanese family with this disorder, and there is no familial relationship to the two previously reported families in Japan.  相似文献   
26.
The vector potential in electrodynamics is investigated through the decomposition of its form to the following two parts: 1) the so-called transverse part represented by a divergenceless vector; and 2) the longitudinal part represented by an irrotational vector. The decomposition can be done by the Helmholtz theorem in the vector analysis because the conditions which should be required when the Helmholtz theorem is used are satisfied for the almost vector potentials of physically interesting problems. As an example of such interesting problems, the Aharonov-Bohm effect is chosen here. As for the Aharonov-Bohm effect, the vector potential given in the original paper of Aharonov and Bohm has the singularities along the z-axis. It is shown that even for such a singular potential the Helmholtz theorem is held provided that the concept of the distribution is introduced in it. Generally, the transverse part of the vector potential obtained through such a decomposition is determined uniquely by the magnetic field and does not alter by a gauge transformation. On the other hand, the longitudinal part depends on the choice of special gauge. It is shown that the Aharonov-Bohm effect is due to the contribution of the transverse part of the vector potential and therefore should not be influenced by any gauge transformations.  相似文献   
27.
In the present paper is analyzed the thermal stress problem of the interaction between an insulated crack and a thin conductive elastic stiffener of finite length bonded to the surface of a semi-infinite medium under uniform heat flow on the basis of the two-dimensional theory of thermoelasticity. The singular point method is adopted to solve the problem and a system of singular integral equations is derived. Numerical results for the thermal-stress intensity factors are presented in terms of normalized parameters which consist of the dimensions and the geometrical arrangement of the crack and the stiffener, and the physical properties of the stiffener and the semi-infinite medium.  相似文献   
28.
Methylcis, cis-, cis, trans- andtrans,trans-9,12-octadecadienoates protect alkaline phosphatase from inactivation by γ-rays. The three isomers are equally efficient.  相似文献   
29.
p-Styrenesulfonate derivatives having cycloaliphatic epoxide in a molecule, were synthesized. Oligomerization of the monomers and co-polymerization of the novel monomers with tert-butyl methacrylate were carried out. When the polymer films containing a photoacid generator (PAG) were irradiated, they became insoluble in solvents. The insoluble films became soluble in water on baking at 120-200 °C. The insolubilization and redissolution profiles were strongly affected by the structure of the monomer, irradiation and baking conditions, and a type of PAG used. The reaction mechanism was studied by TGA analysis and FT-IR spectroscopy.  相似文献   
30.
Atom probe tomography analysis of heavily drawn pearlitic steel wires was performed with and without low-temperature aging. In the as-drawn wire, the lamellar cementite hardly decomposed and remained in a sufficient amount. By contrast, almost homogeneous carbon atomic distribution of the concentration near the average carbon content was observed in the wire with maximum tensile strength aged at 150 °C for 30 min. In the 200 °C × 30 min aging, carbon atoms were enriched at the boundary (prior lamellar cementite) and the carbon concentration in the lamellar ferrite was lower. The change in carbon state was explained by the presence of the high number density of vacancies that was introduced by heavy drawing. These results indicate that cementite decomposition occurred during the thermal aging after, and not during, drawing. The mechanism of the change in strength by low-temperature aging was discussed.  相似文献   
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