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41.
The object of this study was to determine muscle characteristics which might predict meat toughness. Eleven Charolais cattle were slaughtered at approximately 26 months of age and the Longissimus lumborum et thoracis muscle was taken 1 hr post mortem and stored at 12 °C for 24 hr and then at 4 °C.

The average half-life for ageing in these raw muscles was 4.6 days but the toughness varied widely between the animals. Toughness varied 3-fold and the rate of ageing varied 20-fold between animals.

Correlations were done to determine which characteristics might explain this variability. Toughness was correlated positively with increase in oxidative status of muscle and the initial levels of calpastatin. Toughness was correlated negatively with the initial levels of μ- and m-calpains and cysteine and serine proteinase inhibitors, the initial pH values and the rates of their decline. The rates of ageing were highly correlated positively with the initial levels of proteinase inhibitors and the rates of decline of calpastatin and negatively with the ultimate amounts of expressible juice.

There was a wide variability in tenderness in M. Longissimus lumborum et thoracis from similar animals. Variations in metabolism and enzyme activity controlled by inhibitors and calpains appear to be largely responsible for this variability.  相似文献   

42.
In the present work, we have investigated the sorption efficiency of treated olive stones (TOS) towards cadmium and safranine removal from their respective aqueous solutions. TOS material was prepared by treatment of olive stones with concentrated sulfuric acid at room temperature followed up by a subsequent neutralization with 0.1 M NaOH aqueous solution. The resulting material has been thoroughly characterized by SEM, energy-dispersive X-ray (EDX), MAS (13)C NMR, FTIR and physicochemical parameters were calculated. The sorption study of TOS at the solid-liquid interface was investigated using kinetics, sorption isotherms, pH effect and thermodynamic parameters. The preliminary results indicate that TOS exhibit a better efficiency in terms of sorption capacities toward the two pollutants (128.2 and 526.3 mg/g for cadmium and safranine, respectively) than those reported so far in the literature. Moreover, the sorption process is ascertained to occur fast enough so that the equilibrium is reached in less than 15 min of contact time. The results found in the course of this study suggest that ion exchange mechanism is the most appropriate mechanism involved in cadmium and safranine removal. Finally, the sorption efficiency of TOS is compared to those of other low-cost sorbents materials yet described in the literature.  相似文献   
43.
We retrospectively studied 369 cases of knee osteoarthritis in 240 patients seen at the Cocody Teaching Hospital in Abidjan, Ivory Coast, from November 1984 through March 1989. There were 126 cases (34.14%) of patellofemoral osteoarthritis, 104 cases (28.18%) of femorotibial osteoarthritis and 139 cases (37.66%) of global knee osteoarthritis (defined as patellofemoral and femorotibial osteoarthritis in the same joint). There was a marked female bias (80.42% of patients). Onset was earlier in patellofemoral osteoarthritis (51.25 years) than in femorotibial osteoarthritis (57.85 years). Half the patients (51.25%) were housewives. The Akan and Mandé ethnic groups contributed 61.54% and 33.03% of patients, respectively. Obesity was present in 19.04% of cases of patellofemoral osteoarthritis and in 10.57% of cases of femorotibial osteoarthritis. Of the patients with femorotibial osteoarthritis, 20.20% had a history of arthritis of the knee and of those with global knee osteoarthritis, 12.23% reported a prior injury to the knee. Varus deformity was found in 24.03% and valgus deformity in 19.23% of the patients with femorotibial osteoarthritis.  相似文献   
44.
The genotoxic effects of air pollutant exposures have been studied in people living and working in Map Ta Phut, Rayong province, Thailand, a site where is located the Map Ta Phut Industrial Estate (MIE) one of the largest steel, refinery and petrochemical complex in the South-Eastern Asia. This was done by the conduction of a transversal study aimed to compare the prevalence of bulky DNA adducts in groups of subjects experiencing various degree of air pollution. DNA adduct analysis was performed in the leukocytes of 201 volunteers by the (32)P-postlabelling assay: 79 were workers in the MIE complex, including 24 refinery workers, 40 steel workers and 15 tinplate workers, 72 were people residing downwind in the MIE area and 50 were residents in a control district of the same Rayong province but without industrial exposures. The groups of workers were analyzed separately to evaluate if DNA adduct formation differs by the type of industry. The levels of bulky DNA adducts were 1.17+/-0.17 (SE) adducts/10(8) nucleotides in refinery workers, 1.19+/-0.19 (SE) in steel workers, 0.87+/-0.17 (SE) in tinplate workers, 0.85+/-0.07 (SE) in MIE residents and 0.53+/-0.05 (SE) in district controls. No effects of smoking habits on DNA adducts was found. The multivariate regression analysis shows that the levels of DNA adducts were significantly increased among the individuals living near the MIE industrial complex in respect to those resident in a control district (p<0.05). In the groups of occupationally exposed workers, the highest levels of DNA adducts were found among the workers experiencing an occupational exposure to polycyclic aromatic hydrocarbons, e.g. the steel factory and refinery workers. When we have evaluated if the levels of DNA adducts of the PAH exposed workers were different from those of the MIE residents, a statistical significantly difference was found (p<0.05). Our present study indicates that people living near point sources of industrial air pollution can experiment an excess of DNA adduct formation. The emissions from the MIE complex are the main source of air pollution in this area and can be the cause of such increment in the levels of DNA damage.  相似文献   
45.
Temporary urbanism is attracting worldwide attention and has been praised for its capacity to transform socio-political and physical spaces, while at the same time it has been criticized for its tacit instrumentality as vehicle for the progressive gentrification of the urban environment. A closer look at temporary urbanism reveals a myriad of practices, initiated by a great variety of actors with diverse ways of operating and taking place in a wide range of environments. Rooted in assemblage theory, we situate our design practice in the specificity of an underused space surrounding social housing blocks in Gateshead, explore manifestations of habitus and the capacity of temporary urbanism to reveal and engage with socio-spatial struggles.  相似文献   
46.
Core/shell microcapsules with low‐permeability membranes and controlled morphology are crucial for the delivery and controlled release of fragrance molecules, pharmaceuticals, inks, or vitamins. Design criteria for next generation microcapsules must include chemical and mechanical stability, and also provide enhanced substrate interactions to improve deposition onto relevant complex surfaces. Here, a coupled approach is presented to synthesize core/shell delivery systems by interfacial polymerization to enhance both the microcapsule–substrate interactions and the mechanical properties of the capsules to induce a burst‐type release. By combining membrane synthesis, nonlinear mechanics, interfacial rheology, analysis of mass transfer, and capsule morphology generated during interfacial polymerization, large permanent deformations into the capsule geometry are programmed, resulting in chemically stable, yet mechanically rupturing microcapsules with anisotropic geometry. To promote interactions and capsule adhesion onto complex substrates, the capsule contact area is controlled to form prominent “suction cup” shaped rims. These capsules have favorable, far‐reaching electrostatic interactions with oppositely charged substrates such as glass, hair, skin, or fabric. By modulating membrane mechanical properties and morphology during synthesis, formulation‐independent physical criteria are used to improve the overall performance of a functional delivery system while expanding knowledge of the key parameters influencing the interfacial polymerization process and membrane formation.  相似文献   
47.
We investigate the formation of bioactive/inorganic coprecipitates of polyphenols catechins with calcium carbonate and calcium phosphate. Extracted from the leaves of Camellia sinensis, green tea catechins are efficient free radical scavengers, but their purported benefits from the perspective of prevention, health, and nutritional physiology are accompanied by unpleasant organoleptic characteristics: they are notoriously bitter. Selective complexation of polyphenols with metal salts is a possibility to mask or inactivate bitterness and/or off-flavors. We produce such complexes using a continuous coprecipitation process. With excess calcium chloride present in the matrix we observe a correlation of the carbonate to total anions molar ratio with the catechin load. To characterize the composition and structure of the coprecipitates we combine elemental analysis, scanning electron microscopy, X-ray powder diffraction, and liquid chromatography coupled to tandem mass spectroscopy (LC/MS-MS). We quantify the release kinetics in different model environments to predict the behavior of the catechins from the coprecipitates in model media simulating the conditions during oral ingestion and storage. The dissolution data suggest that the release profile of these delivery systems can be influenced and fine-tuned via the anion composition of the mineral carrier.  相似文献   
48.
Delamination process in the multidirectional laminates under bending loading conditions is often accompanied by excessive deformations ahead of the crack tip and non-linearities due to large displacements and transverse microcracks, which appear in the most strained plies especially for thin materials. Since linear elastic fracture mechanics cannot be directly used in order to characterize delamination, our objective is to highlight, experimentally and analytically, the delamination peculiarities on DCB specimens, then to optimize specimen thickness to the value, which makes it possible to avoid the appearance of transverse cracking before starting of delamination. The material used is E-glass/epoxy multidirectional laminates. The results of optimization obtained are in good agreement with the experimental data. __________ Translated from Problemy Prochnosti, No. 6, pp. 66–78, November–December, 2006.  相似文献   
49.
Dodecylsulfate- and dodecyl benzene sulfonate-hydrotalcites were prepared by calcination-rehydratation method. The surfactants intercalation in the interlayer space of hydrotalcite were checked by PXRD and FTIR spectroscopy where the resulting materials were found to be similar to those reported in the literature and were used to remove a basic dye (safranine) from aqueous solutions. The sorption kinetics data fitted the pseudo second order model. The isotherms were established and the parameters calculated. The sorption data fitted the Langmuir model with good values of the determination coefficient. The thermodynamic parameters calculated from Van't Hoff plots gave a low value of Delta G degrees (<-20 kJ mol(-1)) indicating a spontaneous physisorption process. Two regeneration cycles were processed by acetone extraction leading to the same removal capacity of the obtained materials as the original surfactant-intercalated hydrotalcites. The UV-vis spectra of the recovered extracts were similar to the spectrum of safranine, which means that the dye was recovered without any modification.  相似文献   
50.
Staphylococcus aureus, which has its ecological niche in the anterior nares, has been shown to cause a variety of infectious diseases mainly for patients in hemodialysis units. We performed this study to evaluate the prevalence of nasal S. aureus carriage among hemodialysis outpatients, to determine the antimicrobial susceptibility of isolates, to characterize the virulence genes, and to identify associated risk factors. Nares swab specimens were obtained from 70 outpatients on hemodialysis between March and June 2010. Samples were plated immediately onto S. aureus specific media and pattern of antibacterial sensitivity was determined using disk diffusion method. Polymerase chain reaction was used to detect nuc, mecA, and genes encoding staphylococcal toxins. Medical record of patients was explored to determine S.aureus carriage risk factors. Nasal screening identified 42.9% S. aureus carriers with only one (3.3%) methicillin‐resistant S. aureus isolate. Among the methicillin‐susceptible S. aureus isolates, high rate of penicillin resistance (81.8%) has been detected. The identified risk factors were male gender and age ≤ 30 years. Research of virulence factors showed a high genetic diversity among the 30 S. aureus isolates. Twenty‐one (70%) of them had at least one virulence gene, of which 3.3% were Panton‐Valentine leukocidin (lukS/F‐PV) genes. S. aureus carriage must be screened for at regular intervals in hemodialysis patients. Setting up a bacterial surveillance system is one of the strategies to understand the epidemiology of methicillin‐resistant S. aureus, to guide local antibiotic policy and prevent spread of antibiotic‐resistant S. aureus.  相似文献   
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