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91.
Turkey is one of the most energy import dependent countries in the world, suffering deeply from the economic and strategic burdens of oil importation. Our purpose is to determine the factors behind the crude oil import policy of Turkey and to measure their contribution to a well-organized import strategy. We implemented a principle component analysis to construct an Oil Import Vulnerability Index (OIVI) based on four factors, which are crude oil import dependency of primary energy consumption, crude oil import bill as a share of Gross Domestic Product (GDP), non-diversification of import sources, and share of oil in total energy import. The contribution of these factors to the OIVI is found to be approximately equal. While an overall deterioration in the OIVI has been observed during periods of increasing oil prices, better diversification of oil import sources has lead to significant improvements. We suggest Turkish policy-makers implement sound policies, emphasizing diversification of crude oil import sources and reduction of the share of crude oil in primary energy imports to increase energy supply security. This study has also demonstrated that it is possible to construct an index representing crude oil vulnerability caused by import dependency. 相似文献
92.
OBJECTIVE: To review the literature investigating the effects of parental affective illness on children over the past decade. METHOD: A computerized search of articles published over the past 10 years was completed. Articles were reviewed and relevant studies are presented. RESULTS: Over the course of the past 10 years a number of longitudinal studies have confirmed that children of affectively ill parents are at a greater risk for psychiatric disorders than children from homes with non-ill parents. Life table estimates indicate that by the age of 20 a child with an affectively ill parent has a 40% chance of experiencing an episode of major depression. Children from homes with affectively ill parents are more likely to exhibit general difficulties in functioning, increased guilt, and interpersonal difficulties as well as problems with attachment. Marital difficulties, parenting problems, and chronicity and severity of parental affective illness have been associated with the increased rates of disorder observed in these children. CONCLUSION: The presence of depression in parents should alert clinicians to the fact that their children also may be depressed and therefore in need of services. J. Am. Acad. Child Adolesc. 相似文献
93.
AH Bosworth MK Williams KA Albrecht R Kwiatkowski J Beynon TR Hankinson CW Ronson F Cannon TJ Wacek EW Triplett 《Canadian Metallurgical Quarterly》1994,60(10):3815-3832
The construction of rhizobial strains which increase plant biomass under controlled conditions has been previously reported. However, there is no evidence that these newly constructed strains increase legume yield under agricultural conditions. This work tested the hypothesis that carefully manipulating expression of additional copies of nifA and dctABD in strains of Rhizobium meliloti would increase alfalfa yield in the field. The rationale for this hypothesis is based on the positive regulatory role that nifA plays in the expression of the nif regulon and the fact that a supply of dicarboxylic acids from the plant is required as a carbon and energy source for nitrogen fixation by the Rhizobium bacteroids in the nodule. These recombinant strains, as well as the wild-type strains from which they were derived, are ideal tools to examine the effects of modifying or increasing the expression of these genes on alfalfa biomass. The experimental design comprised seven recombinant strains, two wild-type strains, and an uninoculated control. Each treatment was replicated eight times and was conducted at four field sites in Wisconsin. Recombinant strain RMBPC-2, which has an additional copy of both nifA and dctABD, increased alfalfa biomass by 12.9% compared with the yield with the wild-type strain RMBPC and 17.9% over that in the uninoculated control plot at the site where soil nitrogen and organic matter content was lowest. These increases were statistically significant at the 5% confidence interval for each of the three harvests made during the growing season. Strain RMBPC-2 did increase alfalfa biomass at the Hancock site; however, no other significant increases or decreases in alfalfa biomass were observed with the seven other recombinant strains at that site. At three sites where this experiment was conducted, either native rhizobial populations or soil nitrogen concentrations were high. At these sites, none of the recombinant strains affected yield. We conclude that RMBPC -2 can increase alfalfa yields under field conditions of nitrogen limitation, low endogenous rhizobial competitors, and sufficient moisture. 相似文献
94.
The small-signal absorption coefficients of 193- and 213-nm nanosecond laser pulses in bovine corneal tissue have been studied. The absolute reflectance of a planar quartz-cornea interface was measured at various angles of incidence for low-intensity laser irradiation (i.e., pulse fluences 3 orders of magnitude below the ablation threshold). The reflectance-versus-angle data were analyzed by the use of Fresnel theory to estimate the effective complex index of refraction of the tissue. This analysis indicated corneal absorption coefficients of 39,900 ± 9800 cm(-1) at 193 nm and 21,400 ± 4900 cm(-1) at 213 nm. 相似文献
95.
96.
ML Mayer SJ Clark TR Konrad VA Freeman RT Slifkin 《Canadian Metallurgical Quarterly》1999,89(2):164-170
OBJECTIVES: This study assessed the influence of public policies on the immunization status of 2-year old children in the United States. METHODS: Up-to-dateness for the primary immunization series was assessed in a national sample of 8100 children from the 1988 National Maternal and Infant Health Survey and its 1991 Longitudinal Follow-Up. RESULTS: Documented immunization rates of this sample were 33% for poor children and 44% for others. More widespread Medicated coverage was associated with greater likelihood of up-to-dateness among poor children. Up-to-dateness was more likely for poor children with public rather than private sources of routine pediatric care, but all children living in states where most immunizations were delivered in the public sector were less likely to be up to date. Poor children in state with partial vaccine replacement programs were less likely to be up to date than those in free-market purchase states. CONCLUSIONS: While state policies can enhance immunization delivery for poor children, heavy reliance on public sector immunization does not ensure timely receipt of vaccines. Public- and private-sector collaboration is necessary to protect children from vaccine-preventable diseases. 相似文献
97.
NP Camacho L Hou TR Toledano WA Ilg CF Brayton CL Raggio L Root AL Boskey 《Canadian Metallurgical Quarterly》1999,14(2):264-272
Osteogenesis imperfecta (OI), a heritable disease caused by molecular defects in type I collagen, is characterized by skeletal deformities and brittle bones. The heterozygous and homozygous oim mice (oim/+ and oim/oim) exhibit mild and severe OI phenotypes, respectively, serving as controlled animal models of this disease. In the current study, bone geometry, mechanics, and material properties of 1-year-old mice were evaluated to determine factors that influence the severity of phenotype in OI. The oim/oim mice exhibited significantly smaller body size, femur length, and moment of area compared with oim/+ and wild-type (+/+) controls. The oim/oim femur mechanical properties of failure torque and stiffness were 40% and 30%, respectively, of the +/+ values, and 53% and 36% of the oim/+ values. Collagen content was reduced by 20% in the oim/oim compared with +/+ bone and tended to be intermediate to these values for the oim/+. Mineral content was not significantly different between the oim/oim and +/+ bones. However, the oim/oim ash content was significantly reduced compared with that of the oim/+. Mineral carbonate content was reduced by 23% in the oim/oim bone compared with controls. Mineral crystallinity was reduced in the oim/oim and oim/+ bone compared with controls. Overall, for the majority of parameters examined (geometrical, mechanical, and material), the oim/+ values were intermediate to those of the oim/oim and +/+, a finding that parallels the phenotypes of the mice. This provides evidence that specific material properties, such as mineral crystallinity and collagen content, are indicative and possibly predictive of bone fragility in this mouse model, and by analogy in human OI. 相似文献
98.
1. Growing pullets were reared on constant 8, 11 or 14 h photoperiods or given 12 daily increments of 30 min followed by an abrupt 6 h decrease in photoperiod in 14 d cycles from 2 d of age to sexual maturity. 2. Birds on the experimental lighting programme matured earlier than constant 8-h controls, later than 11-h controls but at the same age and body weight as constant 14-h controls. 3. Weight of the first egg was correlated with age at first egg. 4. It is assumed that potential advances in maturity for the experimental birds from the 30 min increments in photoperiod were cancelled by the retarding influences of 6 h decreases in photoperiod, resulting in their maturity being similar to that of birds reared on a constant daylength equal to the longest photoperiod reached during the cycle. 相似文献
99.
100.
Mice transgenic for the leukemia oncogene E2A-PBX1 invariably develop lethal, high-grade T-cell lymphomas by 5 months of age. In this study, retroviral insertional mutagenesis was employed to identify oncogenes that cooperate with the E2A-PBX1 transgene in lymphomagenesis. Neonatal retroviral infection substantially reduced length of survival due to accelerated development of lymphomas (81 versus 130 days). The Pim1 gene was targeted by retroviral insertions in 48% of accelerated lymphomas whereas less than 5% contained activated c-Myc and none contained activated Pim2. However, Pim1 DNA rearrangements were frequently sub-stoichiometric and not present at all sites of involvement in an otherwise monoclonal lymphoma indicating that Pim1 activation occurred late in the course of lymphomagenesis. Tumor subpopulations containing activated Pim1 alleles displayed a substantial growth advantage over Pim1 negative cells following serial transfer to secondary, syngeneic recipients. Cooperative interactions were observed in intercrossed Pim1 and E2A-PBX1 transgenic mice in which all double transgenic progeny developed lethal, diffuse T lineage lymphomas by 3 months of age, whereas only 13% of E2A-PBX1 and none of Pim1 single transgenic intercross progeny developed lymphomas by 1 year. Tumors from double transgenic mice were monoclonal providing evidence that additional genetic events were required for transformation. Therefore, Pim1 and E2a-Pbx1 cooperate in T lineage lymphomagenesis but they are not sufficient and the role of Pim1 is more likely to be associated with tumor progression. 相似文献