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71.
Shelf-life and quality of fresh fishery products can be extended by the use of a modified atmosphere (MA) and high barrier film packaging coupled with refrigerated storage. MAs with elevated levels of carbon dioxide inhibit or slow the growth of various aerobic spoilage bacteria of fishery products by extending the lag phase. However, at the same time, MAs provide conditions for the growth of Grampositive bacteria and food pathogens within the package. The extension of the storage life of the refrigerated MA products may enable the slower-growing Gram-positive bacteria to reach high populations. The shelf-life of fishery products packaged under MAs rich in carbon dioxide coupled with storage at 8.0°C or below can be extended more than 100%. Major safety concerns regarding the risk of foodborne botulism can result from MA packaging of fresh fishery products that contain the spores of nonproteolytic C. botulinum and are subsequently temperature-abused. Minimizing the risk of foodborne botulism by including inhibitory factors such as antimicrobial agents before packaging fishery products under MAs and strict adherence to refrigerated storage temperatures are discussed.  相似文献   
72.
Maximum additions of milk fat that produced temperable milk chocolates were anhydrous milk fat (AMF), middle-melting fraction (MMF) or low-melting fraction (LMF) up to 40 wt % total fat, and high-melting fraction (HMF) up to 35%. The solid fat content (SFC), melting point, melting enthalpy, instrumental and sensory hardness of milk chocolates decreased with increasing milk fat addition. No differences in sensory attributes sweetness, milk powder, chocolate, butter flavor or thickness of melt were observed. Chocolate with 40% MMF or LMF had greater milk flavor than that with 12.2% HMF. Onset of melt correlated (r = 0.96) with melting enthalpy. No differences between types of milk fat (AMF, HMF, MMF, LMF) were observed for any textural attribute assessed.  相似文献   
73.
The Planetary Boundary Layer plays an important role in air pollution meteorology and in fixing the Stack height of major air-polluting industries, including the super thermal power plants. In India a super thermal power plant is being set up at Yamunanagar (30·1° N, 77·33 ° E) and it has been studied using an acoustic sounder with a stack height of 220?m which would be the optimum height to keep the physical stack above surface based inversions for 80 per cent of the time and the elevated inversions for 50 per cent of time above. However, the hot plume rise would inject any pollutants above the surface based inversions for 95 per cent of the time  相似文献   
74.
A set of sensitivity functions are defined in the state space representation of a system. These functions relate ’ small ’ changes in system parameters that inevitably occur in the assembly or the operation of a plant, to the eigenfunctions of the system. The variations of system response of a linear time invariant, dynamical system when it is subjected to parameter variations are the object of this investigation. A new approach for the sensitivity analysis of the system response is indicated. This approach leads to procedures which give rise to fairly routine operations on a digital computer.  相似文献   
75.
76.
Conventional power grids across the globe are reforming to smart power grids with cutting edge technologies in real time monitoring and control methods. Advanced real time monitoring is facilitated by incorporating synchrophasor measurement units such as phasor measurement units (PMUs) to the power grid monitoring system. Several physical and economic constraints limit the deployment of PMUs in smart power grids. This paper proposes a pragmatic multi-stage simulated annealing (PMSSA) methodology for finding the optimal locations in the smart power grid for installing PMUs in conjunction with existing conventional measurement units (CMUs) to achieve a complete observability of the grid. The proposed PMSSA is much faster than the conventional simulated annealing (SA) approach as it utilizes controlled uphill and downhill movements during various stages of optimization. Moreover, the method of integrating practical phasor measurement unit (PMU) placement conditions like PMU channel limits and redundant placement can be easily handled. The efficacy of the proposed methodology has been validated through simulation studies in IEEE standard bus systems and practical regional Indian power grids.  相似文献   
77.
Rice flour and varying amounts (10–35%) of deboned minced carp were coextruded resulting in a precooked blend that developed no detectable offodors after being stored at room temperature for up to six months. In addition, the extrudates, along with nonextruded rice flour, were made into pakodas, a fried Indian snack food. Sensory triangle test data showed that up to 25% carp could be added before a statistical difference was noted. Hedonic sensory data demonstrated that consumer acceptable products relative to pakodas appearance, aroma, flavor, texture and overall acceptability can be made even at carp addition levels of up to 35%.  相似文献   
78.
This study was canied out to evaluate the effect of hardfacing consmaaables on ballistic performance of armour grade quenched and tempered (Q&T) steel welded joints. To evaluate the effect of harclfacilag constuaaables, j ohats were fabricated usilag 4 mm thick tungsten carbide (WC)/ chromium carbide (CrC) hardfaced middle layer; above and below which austenitic stahfless steel (SS) layers were deposited on both sides of the hardfaced interlayer. Shielded metal are weldhag (SMAW) process were used to deposite all (hardfaced layer and SS layers) layers. The fabricated j oints were evaluated for its ballistic peffomamace, and the results were compared with respect to depth of penetration (DOP) on weld metal and heat-affected zone (HAZ) locations. From the ballistic test results, it was observed that both the joints successfully stopped the bullet penen'ation at weld center line. Of the two joints, the joilat made with CrC hardfaced ilaterlayer (CAHA) offered better ballistic resistmace at weld metal. This is because its harchaess is higher due to the presence of primary carbides of needle shape, polyhech'al shape and eutectic matris contaillhag a mixture of γ + M7C3 carbides in the CrC hardfaced interlayer. The scatterilag hardness level ha the WC interlayer, the matrix decomposition resulted lower harchaess and the co-existence of δ ferrite in the ilaterface between hardfacing and SS root/SS cap could be attributed to the lifferior ballistic resistmace of the joint made with WC hardfaced interlayer (WAHA joint).  相似文献   
79.

ABSTRACT

A laboratory scale technique for nonthermal sterilization of green coconut water was developed. The process consisted of two‐stage filtrations under constant pressure using different filter media; namely, low ash filter paper (Whatman 42) in the first stage and cellulose nitrate membrane (0.2‐µm pore opening) in the second stage. The quality of the filtered water was evaluated with respect to microbial population, organoleptic characteristics, nutrient contents and physical properties. The water after the second stage of filtration was sterile with no visible growth of microbes on culture plates. The taste of the processed water did not change significantly; however, the flavor and overall acceptability decreased about 9 and 11%, respectively. The water also remained sterile after 1 month in aseptically packed condition, but overall acceptability further decreased by 6%. The filtration reduced different nutrients of the fresh water like fat, ash, total sugar, reducing sugar and protein by 40.0, 43.9, 23.4, 29.2 and 13.3%, respectively; the removal of K, Mg, Ca, Fe and Cu was 10.15, 16.14, 19.04, 20.85 and 22.21%, respectively. The removal of these nutrients increased surface tension and decreased viscosity of the coconut water.

PRACTICAL APPLICATIONS

Packaging of sterile green coconut water as soft drink has a good global market as it ensures its widespread availability, quantity and reasonable price. Non‐thermal sterilization by membrane filtration has been found to be an alternative to thermal sterilization as the later adversely deteriorates many essential qualities of this delicate coconut water. The present non‐thermal sterilization technique maintained the sterility, nutritional quality and desirable organoleptic profile of the processed water. Thus, this process could be applied for production of green coconut water as packaged soft drink.
  相似文献   
80.
We have investigated the current–voltage (IV) and capacitance–voltage (CV) characteristics of Ru/Pt/n-GaN Schottky diodes in the temperature range 100–420 K. The calculated values of barrier height and ideality factor for the Ru/Pt/n-GaN Schottky diode are 0·73 eV and 1·4 at 420 K, 0·18 eV and 4·2 at 100 K, respectively. The zero-bias barrier height (Φb0) calculated from IV characteristics is found to be increased and the ideality factor (n) decreased with increasing temperature. Such a behaviour of Φb0 and n is attributed to Schottky barrier (SB) inhomogeneities by assuming a Gaussian distribution (GD) of barrier heights (BHs) at the metal/semiconductor interface. The current–voltage–temperature (I–V–T) characteristics of the Ru/Pt/n-GaN Schottky diode have shown a double Gaussian distribution having mean barrier heights ( [`(F)]\textb0 {\bar{{\Phi}}_{\text{b}0}} ) of 1·001 eV and 0·4701 eV and standard deviations (σ 0) of 0·1491 V and 0·0708 V, respectively. The modified ln (J0 /T2 )-( q2s 02/2k2T2 ){ln} ({{J}_{0} /{T}^{2}} )-( {{q}^{2}{\sigma} _{0}^{2}/{2}{k}^{2}{T}^{2}} ) vs 103/T plot gives [`(F)]\textb0 \bar{{\Phi}}_{\text{b}0} and Richardson constant values as 0·99 eV and 0·47 eV, and 27·83 and 10·29 A/cm2K2, respectively without using the temperature coefficient of the barrier height. The difference between the apparent barrier heights (BHs) evaluated from the IV and CV methods has been attributed to the existence of Schottky barrier height inhomogeneities.  相似文献   
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