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1.
Many occupations require workers to stand for long periods of time without proper interventions, which causes discomfort in the back and lower limbs. Therefore, this study aims to assess the effectiveness in alleviating body muscle discomfort during prolonged standing through the use of a calf massager. This study was conducted among male workers at a manufacturer with production line workers and the list was obtained from the HR Department and simple random sampling was done by number categorization. A total of 100 respondents (50 respondents for both the control and the experimental groups) participated in this study. The experiment took place in a room with a similar setup for the production line. Each respondent was requested to perform the simulated task for 2 hr. For the experimental group, the calf massager was turned on every 15 min. At every 15‐min interval after turning on the calf massager, respondents from both groups were required to evaluate their discomfort level on a Borg's scale CR‐10 questionnaire. The results showed that the level of body discomfort among respondents in the experimental group reduced (20–30%) compared with that of the control group. Multivariate analysis results revealed that the discomfort rating for the lower back, knees, thighs, calves, and feet was significantly lower (p < .05) among the experimental group compared with the control group. For lower body parts, the lower back region was statistically significant (p < .05) at the 90th, 105th, and 120th min; the thigh region was statistically significant (p < .05) at the 120th min; the knee region was statistically significant (p < .05) at the 105th and 120th min; the calf region was statistically significant (p < .05) at all minute intervals except the 15th and 45th min, while the feet region, was statistically significant at the 105th and 120th min. Therefore, this study indicates that calf massage treatment is capable of reducing body muscle discomfort during prolonged standing and highlights the significance of calf massage.  相似文献   
2.
In the present study, the influence of citric acid (CA) on hydrogel films composed of sodium carboxymethylcellulose (NaCMC), hydroxypropylmethylcellulose (HPMC), and CuO nanoflakes was investigated for their physicochemical, mechanical, thermal, and antibacterial properties. XRD patterns showed that the prepared hydrogel films revealed the crystalline phase for CuO/Cu2O/Cu at 20% CA concentration. Laser micro-Raman spectroscopy confirmed the presence of CuO and Cu2O in the films. Increase in CA concentration decreased the swelling degree and tensile strength and increased the decomposition temperature of NaCMC, HPMC, and CuO. According to FESEM and FETEM results, shape and size of CuO nanoflakes were completely changed into spherical nanoparticles with increase in CA concentration. HRTEM and inverse Fourier transform images showed that the d-spacing of CuO, Cu2O, and Cu were correlated with XRD results. The prepared hydrogel films exhibited significant antibacterial activity and biocompatibility against HaCaT cells. All these data recommend that the prepared hydrogel films may be used for potential wound healing applications.  相似文献   
3.
Journal of Materials Science: Materials in Electronics - Pseudo-capacitors are the emerging energy storage devices which forms a bridge between batteries and conventional capacitors. In the present...  相似文献   
4.
Researchers have derived inspiration from the biophotosynthetic structures in nature and have started to synthesize the modified bioinspired solar cells copying the evolved organic and inorganic material properties. One of the highlighted examples of bioinspired photo voltaic (PV) cells is the astonishing achievement of an increase in the absorption of integrated sunlight waves in unpatterned solar cells simulated from the wings of the butterfly. Further, deployment possibilities of incorporating flexible cells on flat or curved surfaces for optimizing performance are also under progress. This article mainly discusses the recent concepts of bioinspired solar cells at the research and development level with the prospects and challenges that lie ahead in the upcoming field of photovoltaic renewable energy cell technology. Different potential materials found suitable for bioinspired solar cells construction are reviewed with their particular challenges.  相似文献   
5.
Hydrogen (H2) is one of the most promising renewable energy sources, anaerobic bacterial H2 fermentation is considered as one of the most environmentally sustainable alternatives to meet the potential fossil fuel demand. Bio-H2 is the cleanest and most effective source of energy provided by the dark fermentation utilizing organic substrates and different wastewaters. In this study, the bio-H2 production was achieved by using the bacteria Acinetobacter junii-AH4. Further, optimization was carried out at different pH (5.0–8.0) in the presence of wastewaters as substrates (Rice mill wastewater (RMWW), Food wastewater (FWW) and Sugar wastewater (SWW). In this way, the optimized experiments excelled with the maximum cumulative H2 production of 566.44 ± 3.5 mL/L (100% FWW at pH 7.5) in the presence of Acinetobacter junii-AH4. To achieve this, a bioreactor (3 L) was employed for the effective production of H2 and Acinetobacter junii-AH4 has shown the highest cumulative H2 of 613.2 ± 3.0 mL/L, HPR of 8.5 ± 0.4 mL/L/h, HY of 1.8 ± 0.09 mol H2/mol glucose. Altogether, the present study showed a COD removal efficiency of 79.9 ± 3.5% by utilizing 100% food wastewater at pH 7.5. The modeled data established a batch fermentation system for sustainable H2 production. This study has aided to achieve an ecofriendly approach using specific wastewaters for the production of bio-H2.  相似文献   
6.
We report herein an efficient and mechanistically unique tandem chemoselective 1,2‐/1,4‐migration of the thio group in keto thioesters that provides substituted butenolides in moderate to excellent yields. Thus, α‐keto thioesters in the presence of stabilized phosphonate carbanions undergo tandem 1,2‐sulfur migration; whereas 1,4‐migration of the thio group has been achieved with the same thioesters after the treatment with Wittig reagents followed by BF3⋅OEt2‐catalyzed tandem reaction. The crossover experiments and the isolation of intermediates reveal a stepwise mechanism for both of these transformations.

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7.
The effect of pasteurization and retort processing on spectral, morphological, thermal, physico‐mechanical, barrier and optical properties of three different packaging materials viz., PP/N6/PP, PET/N6/cPP and SiOx‐PET/N6/cPP were studied. These packaging materials were packed with distilled water, which acted as a food simulant. Subsequently, these pouches were subjected to different thermal processing conditions such as pasteurization and retort processing. Both the processing techniques found to have retained the mechanical properties of all packaging materials. Water vapour transmission rate (WVTR) and oxygen transmission rate (OTR) of nylon‐based combinations were increased after processing. Gloss found to decrease invariably irrespective of the material and increases with the severity of the treatment. XRD diffractogram shows changes in crystal structure as a result of thermal processing, and SEM analysis shows the crystal fragmentation. Absorption of water by the amide group of nylon 6 was observed, which could be a reason for the increase in OTR and WVTR. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
8.
A concentrated solar absorber with finned phase change materials was experimentally studied using a Scheffler type parabolic dish concentrator. The absorber's inner surface was fixed with hollow cylindrical containers filled with phase change material (PCM) for heat transfer augmentation. The absorber's selected PCM was acetanilide (Melting point of 116 °C)—the cylindrical capsules protruding into the fluid side to create turbulence and mixing and acting as fins. The absorber surface temperature was observed to be about 130–150 °C during the outdoor tests while passing fluid through the absorber. The fluid flow rate varied from 60 to 100 kg/h during the outdoor experiments. The peak energy and exergy efficiency of parabolic dish collector (PDC) at the fluid flow rate of 80 kg/h with PCM integrated solar absorber was found to be about 67.88% and 6.96%, respectively. The integration of cylindrical PCM containers resulted in more heat transfer augmentation in the solar absorbers. The optimized solar absorber could be suitable for various applications like steam generation, biomass gasification, space heating, and hydrogen generation.  相似文献   
9.
Psychological distress and disabilities are increasingly identified among general population. Psychiatrist availability in rural areas is poor and often general practitioners have to identify and treat psychiatric problems like depression and anxiety. This work proposes a method to identify the psychiatric problems among patients using multimodel decision support system. Backpropagation neural networks (BPNN), radial basis function neural network (RBFNN) and support vector machine (SVM) models are used to design the decision support system. Forty-four factors are considered for feature extraction. The features are collected from 400 patients and divided into four sets of equal size. Three sets of patient features are used to train the decision support system and one set of patient feature are used to evaluate performance of the system. Experimental results show that the proposed method achieves an accuracy of 98.75% for identifying the psychiatric problems.  相似文献   
10.
β‐eucryptite (LiAlSiO4), a member of the family of lithium aluminum silicates, is known to undergo a reversible pressure‐induced phase transformation at ~0.8 GPa to ε‐eucryptite. This study correlates the results between two techniques, in situ diamond anvil cell–Raman spectroscopy and nanoindentation experiments, to explore how doping (substituting Zn for Li) influences this pressure‐induced phase transformation. Diamond anvil cell tests carried up to 3 GPa hydrostatic stress under Raman spectroscopy were compared with nanoindentation results, which provide a more localized, multiaxial stress state. The results indicate that the magnitude of hysteresis observed (difference between the pressures required for the forward and reverse transformation) is lower for Zn‐doped β‐eucryptite; however, the onset of the phase transformation is unchanged by doping with Zn. Furthermore, calculations of activation volume from nanoindentation experiments yield similar values (~0.1 nm3) for pure and Zn‐doped β‐eucryptite, suggesting that the nucleation event that establishes the onset of the phase transformation is the same for both materials.  相似文献   
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