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101.
Peptides obtained by enzymatic hydrolysis of fish proteins exhibit not only nutritional but also biological properties of dietary uses, or even therapeutic potential. The objective of the present study was to isolate and characterize peptides from the protein hydrolysates of barbel muscle with antibacterial activity against Gram-positive (Listeria monocytogenes, Staphylococcus aureus, Enterococcus faecalis, Micrococcus luteus and Bacillus cereus) and Gram-negative (Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa, Klebsiella pneumoniae and Enterobacter sp.) bacteria. Barbel muscle protein hydrolysates (BMPHs), obtained by treatment with Alcalase® (DH = 6.6%), was fractionated by size exclusion chromatography on a Sephadex G-25 and purified by reversed-phase high performance liquid chromatography (RP-HPLC). The molecular masses and amino acid sequences of these peptides were determined using ESI–MS and ESI–MS/MS, respectively. Eleven peptides in FII-1, FII-2, FII-3 and FII-4 sub-fractions separated by RP-HPLC were identified. The most active peptide fraction (FII-3) contained three peptides: Ala–Ala–Ala–Leu; Ala–Ala–Gly–Gly–Val and Ala–Ala–Val–Lys–Met.  相似文献   
102.
This paper proposes an approach for measuring performance improvement through prioritising and aggregating performance indicators (PIs). The proposed approach helps practitioners build, in a formal way, their performance measurement systems. The novelty of the methodology lies in: (i) adapting PIs to specific industrial contexts according to companies concerns and (ii) supporting the decision-making process by providing a holistic and limited number of aggregated PIs. The context considered in the current research is sustainable mass customisation (SMC). Accordingly, a set of SMC indicators are used to illustrate the applicability of the methodology. The implementation and illustration with a real case showed some evidence of its usefulness and pointed out several improvement rooms.  相似文献   
103.
Composite materials that combine the lithium exchanging material LiCoO2 and the conductive polymer poly(aniline) (PANI) have been investigated regarding their possible application to electrode materials of lithium batteries. Such composite materials have been prepared by means of polymerization of aniline in acidic suspensions of LiCoO2 particles. PANI was synthesized by oxidative polymerization of aniline by ammonium persulfate in the presence of sodium dodecylbenzenesulfonate (SDBS) as a micellar template and dopant. The composite material consisted in LiCoO2 particles dispersed in a continuous matrix of PANI. The ribbon-like morphology of the powdered material was distinctly different of the morphologies of the parent materials. The conductive material had conductivity close to that of PANI because the LiCoO2 content of the composite material was low. The presence of the poorly conductive inorganic phase caused a significant loss of conductivity, showing that LiCoO2 blocked electronic transfers between PANI crystallites. Ammonium persulfate caused the loss of lithium from LiCoO2 when it was used at high concentration in the polymerization recipe. In this case a new phase made of Co3O4 formed by chemical decomposition of LixCoO2. Thin films prepared from stable suspensions of composite materials in water show comparable electrical performance to that measured for bulk materials.  相似文献   
104.
Crystals of NaEuP2O7 have been grown by the flux technique and characterized by X-ray diffraction. Single crystal structure of NaEuP2O7 has been solved, for the first time; it crystallizes in the monoclinic P21/n space group with lattice parameters : a = 5.238(2), b = 8.443(4), c = 12.486(6) Å, β = 91.404°(2), V = 552.0(4) Å3, Z = 4. The crystal structure has been refined yielding a final R(F2) =0.049 and Rw(F2) = 0.138 for 1313 independent reflections (Fo2 ≥ 2σ(Fo2)). In this structure, the PO4 tetrahedral are linked by bridging oxygen to give P2O7 groups, these groups are connected to the EuO8 polyhedron by sharing two oxygen corners to form three-dimensional framework in which channels are noticed and where the sodium ions are located. The frequencies of the vibrational modes of the crystal were obtained from measurements of the infrared spectra.  相似文献   
105.
106.
This paper examines the role of drawbead design within tooling design and stamping engineering, as a system. A microcomputer based program DRAWBD is used to illustrate the effect of tooling adjustments beyond and within the trim line, the variability of material and lubricant on the part thickness, as well as stress and moment distributions. The paper illustrates that the interactions between the different tooling and operational parameters are very complex, and demonstrates the difficulty in troubleshooting drawbead controlled stamping systems. The conclusion is that the goal in stamping should be to maintain control over the tooling, process, and material windows, and accordingly over uniformity and consistency of interacting parameters.  相似文献   
107.
Olive oil represents an important ingredient in the Mediterranean diet and is appreciated both for nutritional and sensory properties, often related to geographical origin and cultivar of olive fruits employed. Fraudsters trying to seek financial gain can adulterate the product causing economic repercussions and, sometimes sanitary risks. The “protected designation of origin” (PDO) label insures a relative protection of both consumers and honest producers, since it prescribes production techniques and specific geographical origin, but one of the main problems is to set down objective tools to control these specifications. We reviewed numerous studies using various analytical tools to discriminate PDO olive oils’ geographical origin depending on (1) volatiles compounds, (2) fatty acid and triacylglycerol composition, (3) trace elements, and/or (4) stable isotope ratios, but we highlighted that, despite their efficiency, none of them could provide an irrefutable identification. However, 87Sr/86Sr signature revealed to be an optimal geographical fingerprint in the same purpose for other food products like cereals, orange juice, coffee or alcoholic beverages. Such 87Sr/86Sr studies do not exist on olive oils, probably because of analytical issues, but we propose that developing complementary 87Sr/86Sr studies could be a promising tool to re-enforce the characterization of PDO olive oils.  相似文献   
108.
A novel concept of air heater using a heating element made from Aluminum metal porous disc surrounded by a DC resistive electrical heater inserted in the mid-plane of a copper tube of (52.8 mm) diameter and (480 mm) length is presented herein. Study of the developed heater is conducted; using different porous disc thicknesses of (20, 40, 60 mm), heater wall temperatures (106 °C and 119 °C), and flow rates rare varied from (100-300 L/min). Al-metal foam disc has been made using the metal powder technology. Different resistive electrical heaters according to the type of porous disc used have been manufactured. A 2-D computational model is developed, using continuity, momentum, and energy equations for turbulent forced flow in plain tube, while adopting Darcy’s model in the porous disc region.  相似文献   
109.
Kaolin porous support ceramic was prepared from kaolin. The characterization of the porous properties and structure of the support synthesis was carried out by scanning electron microscopy (SEM), absorption rate, shrinkage rate and Hg-porosimetry methods. The pore size distribution showed a unimodal pore size distribution with an average pore size of about 0.9 µm. The reliability of support was measured by filtration tests and removal of heavy metals.Filtration studies using porous tubular supports were performed for solutions containing methylene blue and Evans blue. The study of the liquid filtration and flow through these supports showed that the methylene blue rejection rate was 99% while the Evans blue rate reached 90% for a 90 minute filtration time under a pressure of 2 bar. We beforehand tested the flow rate for each support with distilled water and the results show that the support of kaolin gave a flux for distilled water of 31.0 L/h at the pressure of 2 bar. At a pressure of 3.5 bar an increase in the distilled water flux through the support was observed.The rejection rate of cadmium ions was more significant. A rejection rate of 99.99% using a 10− 4 mol/L solution of this heavy metal for two-hour treatment time was obtained.  相似文献   
110.
In this paper, we are interested in addressing risk analysis. We propose an influence diagram-based approach that focuses on a Benefit, Cost, Deficit (BCD) model. The BCD model is proposed for studying the intentional deviant behaviors of human operators in a system. In this model, the consequences of human actions are analyzed with respect to three parameters: benefit, cost and deficit. Our approach aims to expand the BCD model by integrating factors, such as those related to the organization of the system in question, that influence human operator actions. In addition, the approach considers multiple criteria that are related, for example, to safety and productivity. To build a model that evaluates the risk induced by human actions in a system and analyzes the impact of the different factors, we use influence diagrams. Influence diagrams are probabilistic graphical models that can deal with uncertainty and with incomplete and imprecise information. Influence diagrams also represent the interdependencies between the different variables of the studied problem. In addition, contrary to Bayesian networks, influence diagrams can rank a set of actions by providing information on which action carries the greatest risk or the most benefits. We applied this approach to a case study of an industrial rotary press, but it can also be used in other problems and sectors.  相似文献   
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