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81.
The superconductivity of the tight binding electrons in a magnetic field is studied. We can treat both cases of quasi-one-dimension and quasi-two-dimension in the same manner. We study a various kind of anisotropic superconductivity with line nodes of the energy gap by taking attractive interaction between electrons in nearest sites along each axis. The magnetic field dependence of the transition temperature is calculated for a various pairing symmetry of superconductivity. When a magnetic field is applied in the conducting plane, the transition temperature is shown to increase as the magnetic field increases. In the strong magnetic field the eigenstates approach to those in the absence of hopping between planes, resulting in no orbital frustration. 相似文献
82.
83.
K Hirai J Pan H Shimada T Izuhara T Kurihara K Moriguchi 《Journal of electron microscopy》1999,48(3):289-296
The generation of oxygen free radicals was investigated using cytochemistry and its energy-filtering transmission electron microscopy in reference to the toxic mediator for the herbicide paraquat. When isolated intact mitochondria from rat livers were incubated in a medium containing paraquat and NADH, a mitochondrial NADH-quinone oxidoreductase activity generated superoxide anions to cause the destruction of mitochondria which resulted in cell death. The superoxide anions were immediately converted into hydrogen peroxide, which then formed cerium perhydroxide deposits in the presence of cerium ions and precipitated on the outer surface of the mitochondrial outer membrane. This localization was also specifically identified by energy spectral imaging and image-electron energy loss spectral analyses. Precipitation reaction was scavenged by the addition of either cytochrome c or catalase and inhibited by dicoumarol (an inhibitor of NAD(P)H-quinone oxidoreductases). These cytochemical energy-filtering transmission electron microscopic results indicated that paraquat generated free radicals from the outer membrane of mitochondria. 相似文献
84.
GQ Zhang A Hotta T Ho T Yamaguchi H Fukushi K Hirai 《Canadian Metallurgical Quarterly》1998,42(6):423-428
The 27-kDa outer membrane protein from eight strains of Coxiella burnetii was expressed in the pET-21c protein expression system. Two fusion proteins with molecular masses of 30 and 32 kDa were evident in all eight of the recombinants by SDS-PAGE and immunoblotting. A protein having an approximate size of 30 kDa was purified from the Escherichia coli lysates by one-step affinity purification. The utility of the purified recombinant protein in ELISA was also evaluated by testing its reactivity with human sera and comparing this reactivity with that of Nine Mile phase II antigen. All of the 40 IF-positive serum samples were ELISA-positive for both the Nine Mile phase II and recombinant antigens, and negative serum controls were negative for both antigens. These results suggest that ELISA with the 27-kDa recombinant antigen is a sensitive and specific method for detecting anti-C. burnetii antibodies in human sera. 相似文献
85.
T Koshino S Takano T Houjo Y Sano K Kudo H Kihara S Kitani T Takaishi K Hirai K Ito Y Morita 《Canadian Metallurgical Quarterly》1998,247(2):510-513
Hormone-sensitive lipase (HSL) catalyzes the rate-limiting step in adipocyte lipolysis. We have studied the effect of glucose and long chain fatty acids on the HSL mRNA content of 3T3-F442A adipocytes. Exposure of the cells for 32 h to a medium without glucose led to a decrease by a factor of 2.5-3 in the HSL mRNA without a change in C/EBP alpha mRNA or triglyceride content of the adipocytes. The reduction in HSL mRNA level was accompanied by a decrease in HSL total activity. The effect of glucose exposure was observed after 24 h of exposure and was reversible. Treatment of the adipocytes with oleate did not affect HSL expression. These data show that glucose modulates HSL gene expression and hence could participate in the regulation of adipose tissue lipolysis. 相似文献
86.
87.
S Isobe A Ando M Nanasato M Nonokawa H Izawa T Sobue M Hirai K Ito T Ishigaki T Murohara M Yokota 《Canadian Metallurgical Quarterly》2003,24(10):1071-1080
This study aimed to determine whether combined examinations of myocardial 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) and stress-redistribution 201Tl single-photon emission computed tomography (Tl SPECT) were useful in clarifying myocardial ischaemia and evaluating the prognosis in patients with idiopathic dilated cardiomyopathy (IDCM). Twenty-two patients with IDCM underwent echocardiography, cardiac catheterization, FDG PET, and Tl SPECT. In scintigraphic analysis, the total defect score (TDS) was semiquantitatively determined as the sum of scores of the 17 left ventricular (LV) segments with a 5-point scale (0 as normal to 4 as absent). Patients were classified according to the scintigraphic findings as follows: eight patients with small defects on Tl and FDG (TDS < or = 20) (group I), eight patients with small defects on FDG (TDS < or = 20) with FDG uptake increased relative to Tl or 'mismatch' (group II), and six patients with large defects on FDG and Tl (TDS >20) (group III). Eleven patients (50%) showed reversible defects on Tl and all showed preserved FDG uptake. The patients in group III had significantly lower LV ejection fraction (LVEF) (P<0.05, respectively) and a poorer prognosis as shown by the Kaplan-Meier event-free curve compared with those in groups I and II (P<0.01, respectively). Although patients in group II had significantly greater TDS on Tl compared with those in group I (P<0.01), no significant differences in LVEF and prognosis were found between patients in groups I and II. In multivariate analysis, a TDS on FDG revealed an independent predictor of subsequent cardiac events. In conclusion, such mismatched areas can be assumed to consist of impaired but viable myocardium, and may be associated with ischaemia of the microvasculature. Impaired myocardial glucose metabolism is a more powerful predictor of future cardiac events than perfusion abnormality in patients with IDCM. 相似文献
88.
K Tahara N Ishikawa K Yamamoto A Hirai K Ito Y Tamura S Yoshida Y Saito LD Kohn 《Canadian Metallurgical Quarterly》1997,7(6):867-877
The majority (97%) of functional epitopes for stimulating thyrotropin receptor (TSHR) antibodies (stimulating TSHRAbs) in a large cohort (n = 59) of Japanese Graves' patients exists on the N-terminal region of the extracellular domain of TSHR, between residues 25 and 165 numbering from the methionine start site. This was determined by measuring the loss of stimulating activity in the Cos-7 cells transfected with TSHR/lutropin-choriogonadotropin receptor (LH-CGR) chimeras wherein TSHR residues 89-165 (Mc2) or 8-165 (Mc1 + 2) are replaced by comparable LH-CGR residues. There is no comparable loss when stimulating TSHRAb activity is measured in an Mc4 chimera, wherein TSHR residues 261 to 370 are replaced. In contrast, immunoglobulin (IgG) preparations from 35 patients with Hashimoto's disease or idiopathic myxedema, who have blocking TSHRAbs causing hypothyroidism, loose blocking TSHRAb activity in the Mc4 chimera, but not the Mc2 or Mc1 + 2 chimeras. Thus, in a large population of Japanese patients with autoimmune thyroid disease caused by TSHR autoantibodies, the major functional epitope for stimulating TSHRAbs is on the N-terminal portion of the TSHR extracellular domain, whereas that for blocking TSHRAbs is on the C-terminal portion of the extracellular domain. To further evaluate the nature of the critical functional epitope between residues 90 to 165, we divided this region approximately in half, creating chimeras Mc2a and Mc2b with, respectively, residues 90-124 or 125-165 replaced by comparable LH-CGR residues. IgGs from all patients tested lost significant stimulating activity using the Mc2a and Mc2b chimeras; however, when present, residual stimulating TSHRAb activity was evident on one or the other half of the region or on both halves, indicating that both segments are required for expression of the stimulating TSHRAb epitope within residues 90-165. Finally, we have identified a complex epitope involving both the N- and C-terminal portion of the extracellular domain that appears to account for the small fraction of stimulating TSHRAbs whose activity is not solely dependent on residues 25 to 165. Thus, using chimeras Mc1 + 2 + 4, with TSHR residues 8-165 and 261-370 substituted, or chimera Mc1 + 2 + 3 + 4, with residues 8-370 substituted, as well as Mc2, Mc1 + 2, and Mc4, we show that the Graves' IgGs which maintain stimulating TSHRAb activity when residues 8-165 of the TSHR are replaced by LH-CGR residues have an epitope involving residues 90-165 and the immunogenic 15mer peptide (YYVFFEEQEDEIIGF), residues, 352-366. Because that peptide can decrease the stimulating TSHRAb activity of these Graves IgGs in assays with the Mc2 chimera alone, we speculate that this complex epitope may be important in an epitope spreading process involved in the formation of stimulating TSHRAbs. 相似文献
89.
Tsuneo Hirai 《Composite Structures》1995,32(1-4):541-548
The principal purpose of this study is to develop a design procedure for a new roll forming process. With SMC, the advantages are reduced forming force and power consumption caused by a spherical stress tensor during compression moulding. Basic information on the deformation behaviour is obtained from a T-shaped profile using carrier type roll forming.
As the SMC is a laminate with heterogeneous properties, consideration must be given to the macroscopic and microscopic interfaces caused by resin-rich surfaces and different stiffnesses of fibre and resin. The effect of feed rate on the flow pattern is also an important problem for the fabrication of different shape products. The fabrication behaviour is investigated with relation to the interfaces in the sequent process to target areas for future development. 相似文献
90.
Highly pure, dense SiB4 and SiB6 plates were prepared by chemical vapor deposition (CVD) at deposition temperatures (TDEP) from 1323 to 1773 K, total gas pressures (Ptottot) from 4 to 40 kPa and B/Si source gas ratios (mB/SI =2B2H6/SiCl4) from 0.2 to 2.6 and their thermoelectrical properties were measured. The Seebeck coefficient (S) of CVD-SiB6 (0.7 mm in thickness), which is known to be a high temperature thermoelectric material, was 320 μVK-1, while its electrical conductivity (s) was 7 Ω -1cm-1, SiB6 + TiB2 and SiB6 + SiB4 in situ composite plates were also prepared to improve the thermoelectric property of CVD-SiB6, The a value of the CVD-SiB6 + 12 wt% TiB2 in situ composite plate (0.7 mm in thickness) was one order of magnitude larger than that of CVD-SiB6 at room temperature, while the figure of merit for the thermoelectric materials (Z) was smaller because of the smaller value of S. However, the Z value of SiBe + 40 wt% SiB4 in situ composite plate (0.5 mm in thickness) was 10-5, larger than that of CVD-SiB6 相似文献