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51.
Proposes a particular ground for moral formulation that is consistent with the consensually based scientific ethic. Researchers' acts of formulating investigatory designs constitute moral values, but these assumptions of value often go unnoticed because they violate the positivist mandate that science should be value neutral. Only a special kind of consensus is "scientific" (as opposed to ideological) because the scientific ethic accepts knowledge as truthful only when it is openly achieved after evenhanded consideration and tested in debate. Since truth in science is a moral issue, close examination should be made of science's moral grounds. The kinds of analyses typically performed by philosophers are an essential part of this empirical search. The author concludes that moral research cannot be "scientific" if this means being value neutral, but it can be scientific in the sense of impartially submitting all formulations to the full reality of people's moral consensuses and interactions in everyday life. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
52.
Dense semicrystalline membranes of polyhydroxyalkanoates with medium change length (PHASCL), polyhydroxybutyrate (PHB) and poly β (hydroxybutyrate-co-hydroxyvalerate) [P(βHB-co-XβHV)] were characterized using wide-angle X-ray (WAXS) and scanning electron microscopy. PHB membranes showed a more rugged surface than those of copolymers (0-22%HV). Properties such as swelling capacity, vapor permeability and selectivity were investigated. Swelling percentage in water-ethanol mixtures was 34% for PHB as compared to 14% for copolymers membranes. The ethanol/water selectivity (αs) of PHB was 5.8 which shows that it is more selective than copolymers.The water vapor and ethanol vapor permeability were determined by a gravimetric technique at different temperatures by static and dynamic methods. PHB permeability was 69.5 Barrer at 30 °C and a discreet increment was observed at temperatures (30-50 °C). The difference in permeability between PHB and [P(βHB-co-X%βHV)] could be interpreted in terms of the crystallization rate, crystallite size and distribution which impact to transport properties of amorphous phase.  相似文献   
53.
Studied the processes of development in 2 moral systems—L. Kohlberg's (1981) and an interactional formulation by N. Haan (1983)—by comparing the effects of 2 curricular experiences. The 2 curricular experiences involved (1) a discussion of hypothetical dilemmas, which was designed to promote cognitive disequilibrium and the playing of moral games, (2) which in turn was designed to promote social disequilibrium. Ss were 119 university students who were members of 15 naturally existing friendship groups of 8 members each. 10 friendship groups played moral games during 5 3-hr sessions; 5 groups discussed hypothetical dilemmas for the same length of time. Individual interviews, held before, immediately after, and 3 mo after these group sessions, provided the bases for constructing developmental indices. Eight moral scores for each moral system—3 interview and 5 session-based—were thereby secured. Other data collected before the session began included measures of characteristic ego functioning and friends' sociometric evaluations, and during the sessions, measures of students' situational ego functioning and the behavior of friendship groups. Development in both moral systems was generally and strongly predicted by positive interactions between individual S's characteristic ego coping and their friendship group's social disequilibrium. Cognitive disequilibrium only occasionally and weakly facilitated moral development in both systems. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
54.
The author replies to 4 previous articles in the present journal (see cases PA, Vol 71:16610, 16604, 16639, and 16594) that criticized her (see record 1983-22367-001) argument that research about morality can be scientific. It is suggested that the assumption that diversity reigns and that there is no moral umbrella for humanity has the effect of relieving social scientists of all responsibility for investigating morality. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
55.
Recombivax-HB (REC) and Engerix-B (ENG) are FDA-approved vaccines for hepatitis B virus (HBV) in end-stage renal disease (ESRD). This study compares antibody response rates between them in routine clinical practice. Patients completing the recommended 40 mug dose of REC (3 doses) or ENG (4 doses) between January 1, 2000 to April 30, 2003 were eligible. Patients with prior positive HBV surface antigen (HBsAg) or antibody (HBsAb) test results were excluded. The conversion rate and persistence of protective titer (HBsAb titer>or=10 IU/mL) were tracked for 1 year. A supplemental analysis of a one-to-one matched patient sample was also performed. REC patients (N=885) were older, had longer dialysis vintage, and had a larger proportion of whites than ENG patients (N=13,661). Cumulative conversion response was greater in ENG (58%) than REC (40%) at 1 year (p<0.0001). The odds ratio for response to ENG compared with REC was 1.96 (95% limits: 1.56, 2.45; p<0.0001) adjusted for age, gender, race, diabetes, vintage, BSA, hemoglobin, and eKt/V. Persistent protective HBsAb after 1 year was 77% (ENG) vs. 53% (REC). HBsAg was positive in 208 ENG patients (1.5%) with all but 1 because of transient, vaccine-related antigenemia. The difference in conversion response favoring ENG persisted in a one-to-one sample matched for age, gender, race, modality, and dialysis vintage. The study found higher seroconversion response to ENG compared with REC at several time points up to 1 year. Protective HBsAb disappeared in 23-47% of patients 1 year later, validating CDC recommendations to re-test HBsAb yearly. The observed difference in response rates may be related to the extra ENG dose given at the second month (0, 1, 2, 6 regimen). The study raises a hypothesis that requires confirmation in a prospective clinical trial.  相似文献   
56.
Multi‐walled carbon nanotubes (CNTs) and cellulose nanofibers (CNFs) reinforced shape memory polyurethane (PU) composite fibers and films have been fabricated via extrusion and casting methods. Cellulose nanofibers were obtained through acid hydrolysis of microcrystalline cellulose. This treatment aided in achieving stable suspensions of cellulose crystals in dimethylformamide (DMF), for subsequent incorporation into the shape memory matrix. CNTs were covalent functionalized with carboxyl groups (CNT‐COOH) and 4,4′‐methylenebis (phenylisocyanate) (MDI) (CNT‐MDI) to improve the dispersion efficiency between the CNT and the polyurethane. Significant improvement in tensile modulus and strength were achieved by incorporating both fillers up to 1 wt% without sacrificing the elongation at break. Electron microscopy was used to investigate the degree of dispersion and fracture surfaces of the composite fibers and films. The effects of the filler (type and concentration) on the degree of crystallinity and thermal properties of the hard and soft segments that form the PU sample were studied by calorimetry. Overall, results indicated that the homogeneous dispersion of nanotubes and cellulose throughout the PU matrix and the strong interfacial adhesion between nanotubes and/or cellulose and the matrix are responsible for the enhancement of mechanical and shape memory properties of the composites. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers  相似文献   
57.
Abstract: In this study, the behavior and enterotoxin production by 10 different coagulase negative Staphylococcus (CNS) strains inoculated in cooked ham, reconstituted skimmed milk, and confectionery cream in the presence or absence of background microbiota have been investigated. After inoculation (103 CFU/g), foods were incubated at 25, 30, and 37 °C and aerobic mesophilic and CNS counts were carried out at 12, 24, 48, and 72 h. Staphylococcal enterotoxins (SE) detection was performed by SET-RPLA (Oxoid, Basingstoke, U.K.) and mini-Vidas® (bioMérieux, La Balme les Grottes, France). CNS counts increased during incubation and approached 106 to 107 CFU/g after 12 h at 37 °C in the 3 foods studied. At 25 °C, counts reached 106 to 107 CFU/g only after 24 to 48 h. The interference of background microbiota on CNS behavior was only observed when they grew in sliced cooked ham, which presented a high initial total count (105 CFU/g). Significantly higher counts of CNS isolated from raw cow's milk in comparison with food handlers isolates were found in reconstituted milk and confectionery cream. Although CNS strains were able to produce SEA, SEB, and SED in culture media, in foods, in the presence or absence of background microbiota S. chromogenes LE0598 was the only strain able to produce SEs. Despite the scarcity of reports on CNS involvement with foodborne disease outbreaks, the results found here support the CNS growth and SE production in foods even in the presence of background microbiota and may affect food safety.  相似文献   
58.
We performed the polymerization of 3-amino-1,2,4-triazole (ATA), an insulator material, in acidic aqueous solution with ammonium persulfate, as oxidant agent. The new material, conveniently doped, turned out to be a semiconductor tetramer. The characterization was carried out using physical and spectroscopic techniques (elemental analysis, infrared spectroscopy, 1H NMR, 13C NMR and mass spectra). Thermogravimetric analysis (TGA) indicated that this oligomer enhances thermal stability of starting material. The room temperature electrical conductivity of the synthesized oligomer (OATA) was 3.1 × 10−4 S cm−1.The kinetic polymerization was analyzed by UV–vis spectroscopy, taking into account the pH dependence, monomer–oxidant ratio and monomer concentration. A possible polymerization mechanism was proposed.  相似文献   
59.
A series of composites based on polydimethylsiloxane‐α,ω‐diol (PDMS) as polymeric matrix, silica aerogel as reinforcing filler, and the lignin powder—a biomass derivative, as bulking filler, have been prepared. Different weight ratios between components were used. The composites were investigated by scanning electron microscopy, dynamic mechanical analysis, tensile strength tests, X‐ray diffraction analysis, thermogravimetric analysis, and differential scanning calorimetry. The results were compared with those obtained on a reference sample prepared by using a classical material—diatomite and a pure crosslinked PDMS. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
60.
Molybdenum carbide has immense potential as an active catalyst for reaction systems such as synthesis of important chemicals like ammonia. However, the carbide is not used as a commercial catalyst or support as the current synthesis processes produce low surface area material or have contaminants such as excess carbon and surface and chemisorbed oxygen. Moreover, attempts to refine the synthesis pathways are usually not supported by any thermochemical modeling. In this study, a facile and reproducible method to synthesize high surface area molybdenum carbide was developed with the help of thermochemical modeling to better understand molybdenum-carbon phase behavior. We have synthesized 2-5 nm particles of MoxC with surface areas of up to 360 m2/g as characterized using a variety of techniques including X-ray diffraction and electron microscopy.  相似文献   
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