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41.
This work reports the application of banana peel as a novel bioadsorbent for in vitro removal of five mycotoxins (aflatoxins (AFB1, AFB2, AFG1, AFG2) and ochratoxin A). The effect of operational parameters including initial pH, adsorbent dose, contact time and temperature were studied in batch adsorption experiments. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and point of zero charge (pHpzc) analysis were used to characterise the adsorbent material. Aflatoxins’ adsorption equilibrium was achieved in 15 min, with highest adsorption at alkaline pH (6–8), while ochratoxin has not shown any significant adsorption due to surface charge repulsion. The experimental equilibrium data were tested by Langmuir, Freundlich and Hill isotherms. The Langmuir isotherm was found to be the best fitted model for aflatoxins, and the maximum monolayer coverage (Q0) was determined to be 8.4, 9.5, 0.4 and 1.1 ng mg?1 for AFB1, AFB2, AFG1 and AFG2 respectively. Thermodynamic parameters including changes in free energy (ΔG), enthalpy (ΔH) and entropy (ΔS) were determined for the four aflatoxins. Free energy change and enthalpy change demonstrated that the adsorption process was exothermic and spontaneous. Adsorption and desorption study at different pH further demonstrated that the sorption of toxins was strong enough to sustain pH changes that would be experienced in the gastrointestinal tract. This study suggests that biosorption of aflatoxins by dried banana peel may be an effective low-cost decontamination method for incorporation in animal feed diets.  相似文献   
42.
The objective of this study was to evaluate the risk of musculoskeletal injuries in a banana processing task. A sample of three workers were evaluated with the Nordic questionnaire as well as according to effort, discomfort and usability levels, hand grip dynamometry, inertial sensor motion capture (Xsens) and surface electromyography in the right arm. The workers had musculoskeletal complaints throughout the spine and hips, low effort and discomfort levels, and a satisfactory usability level. The hand grip strength values (dominant: 54.8 Kgf; non-dominant: 54.2 Kgf) were above the reference values for the Brazilian population. Regarding movement analysis, we identified risks related to cervical protrusion, forward and lateral trunk flexion, abduction and flexion in the shoulders, flexion, extension, radial and ulnar deviation in the wrists, as well as repetitive movements. Surface electromyography showed that the greatest demand during the task was on the extensor carpi radialis, although the trapezius and flexor carpi radialis showed a tendency toward fatigue. Thus, the set of evaluations showed that the tool used and worker adaptation to the position of the bunches, together with the repetitious movement, led to inadequate postures and musculoskeletal risks.Relevance to industryThe banana processing activity generates employment and income in several regions of the world and in Brazil. However, it is still rudimentary and may present risks to the worker's health. This study seeks to elucidate ergonomic risks through technological instrumentation in order to have a quantitative assessment of the ergonomic risks.  相似文献   
43.
Five facultative anaerobic bacterial isolates were recovered from domestic wastewater. These isolates were identified based on the 16S rRNA as Enterobacter aerogenes (one isolate), Enterobacter cloacae (two isolates), and Cronobacter sakazakii (three isolates). These isolates were examined for their potential to evolve hydrogen on a glucose medium. The most potent hydrogen‐producing isolates, E aerogenes (KY549389) and E cloacae (KY524293), were examined for their capacity to generate hydrogen, acetone, butanol, and ethanol using orange peel (OP) hydrolysate. OP powder was pretreated with n‐hexane to remove the toxicity of d ‐limonene. Different concentrations (4%, 6%, and 8% w/v) of limonene‐free OP were subjected to the boiling water (temperature of 100°C) or acid (HCl) treatments. The maximum fermentative H2 production of 1700 and 1620 mL/L was obtained from 6% OP hydrolysate extracted with boiling water using facultative anaerobic E aerogenes (KY549389) and E cloacae (KY524293), respectively. Hydrogen production efficiency was 0.99 and 1.19 mol H2/mol glucose for E aerogenes and E cloacae, respectively. The total fermentative acetone, butanol, and ethanol (ABE) generated by E aerogenes and E cloacae were 0.78 and 0.38 g/L including acetone (0.05 and 0.04 g/L), butanol (0.011 and 0.013 g/L), and ethanol (0.71 and 0.32 g/L), respectively. The maximum ABE productivity was 0.01 and 0.005 g/L/h generated at 60 g/L OP hydrolysate by E aerogenes and E cloacae, respectively. These strains were positive for nitrogen fixation (nitrogenase) capability estimated by the acetylene reduction assay. Application of OP hydrolysate without the addition of any nutritional components or reducing agent is considered an eco‐friendly, economical, and commercial substrate for desired biofuel production.  相似文献   
44.
For many of the developing world's poorest farmers and food-insecure people, roots, tubers, bananas and plantain crops (RTBs) serve as a critical source of food, nutrition and cash income. RTBs have been particularly important in areas where local agri-food systems are under stress. Under such circumstances, growers, processors and traders often see opportunities to improve food security or increase their incomes with those crops due to shifting tastes and preferences for food and non-food products. Since the early 1990s, cassava output surged in sub-Saharan Africa, while potato production expanded rapidly in Asia. RTBs are consumed by over three billion people in developing countries with a market value of US$ 339 billion. This paper analyses the major changes in production, utilisation and trade of RTBs over the last six decades, assesses estimates of their future trajectory and offers recommendations so that they might achieve their full potential.  相似文献   
45.
The culinary banana peel, which is an agricultural waste available in abundance, has not been able to draw much attention in terms of its utilization. In addition to being an abundant source of functional and nutritional compounds, it also deserves to be utilized in a proper and/or better way. The aim of this study was to explore this agro-waste at different levels of maturity in order to identify the active compounds at particular stage of maturity. Phenolics, flavonoids, and radical scavenging activity were maximum at early developmental stage, whereas compounds like protein, fat, carbohydrates, and starch increased with maturity and declined at over-ripe stage. The starch present in the peel is of C-type as confirmed by x-ray diffractograms and crystalline in nature. The peel, at the edible mature stage 4, yielded a high cellulose content which could be used as a reinforcement material in high-performance biocomposites. The presence of various functional groups indicating the complex nature of the culinary banana peel was confirmed by Fourier transform infrared characterization. Scanning electron microscope micrographs revealed that microstructure of peel changes drastically and degradation of starch and other compounds occurred at the over-ripe stage. Hence, in this context, the culinary banana peel can serve as a potential biomaterial in industrial applications and can add a higher value to this locally important and underutilized crop.  相似文献   
46.
Antioxidant potential and bioaccessibility of co‐products from industrial pasteurised pomegranate nectar (PN) processing such as peel (PP), press cake (PC) and precipitate after clarification (PAC) in comparison with raw material (arils) and final products (CON and PN) were determined. Total phenolic (TPC), flavonoid (TFC), anthocyanin (TAC), tannin contents (TTC) and antioxidant activity (TAA) were determined besides identifying major phenolics and investigating in vitro bioaccessibility after gastrointestinal (GI) digestion. PP showed the highest values, except for TAC. Phenolics (12.7–43.0%) were found to be more stable than anthocyanins (0.6–2.1%) after in vitro GI digestion. PAC was found to be a better source for anthocyanins than CON and also showed higher phenolic bioaccessibility (28.8%) than PN (19.6%). PC and PAC possessed as much TPC, TFC, TTC and TAA levels as CON, with some exceptions. Therefore, these results indicated that not only PP but also PC and PAC should be valorised as a good source for phenolics and anthocyanins.  相似文献   
47.
Pomegranate peel powders were prepared by superfine grinding, whose effects were investigated on the composition, functional and antioxidant properties of the pomegranate peel products. Fluidised bed jet milling technology was used to process superfine pomegranate peel powder. The physical–chemical properties of coarse powder A (D50 = 413.4 μm) and B (D50 = 197.1 μm), fine powder C (D50 = 142.6 μm) and D (D50 = 41.2 μm), superfine powder E (D50 = 7.68 μm) and raw material powder (RMP) (D50 = 352.2 μm) were investigated in this study. SEM images revealed the shape and surface morphology of six pomegranate peel powders. The physical determinations showed that the smaller the powder particle size was, the greater the surface area (from 0.214 to 1.597 m2 g?1) and bulk density (from 0.653 to 0.751 g mL?1) were, the smaller the angles of repose (from 51.69° to 38.74°) and slide (from 48.32° to 34.18°) were. The water holding capacity (WHC), water‐solubility index (WSI), polyphenols and flavonoids release were significantly improved as the size of pomegranate peel particle decreased. The results of FTIR and UV indicated that grinding process would not influence chemical composition of pomegranate peel. Vitamin C (VC) and butylated hydroxytoluene (BHT) were used in DPPH scavenging activity determination, and DPPH scavenging activity was A < RMP < BHT < B < C < D < E < VC.  相似文献   
48.
Kiwifruit is one of the most popular fruits worldwide, and it has various biological properties, including antioxidant, anti-allergic, and cardiovascular protective effects. The peel of kiwifruit, which is a by-product of processing, is a good source of flavonoids; however, its bioactivity has not been widely investigated. In this study, we evaluated the hypnotic effects of green (GRPE, Actinidia deliciosa) and gold (GOPE, Actinidia chinensis) kiwifruit peel ethanol extracts and their solvent fractions, and the possible underlying mechanisms. Oral GRPE and GOPE administration (125–1000 mg/kg) produced a dose-dependent decrease in sleep latency and an increase in sleep duration in pentobarbital-treated mice. Among three different solvent fractions of GRPE and GOPE, ethyl acetate (EA) fractions had the greatest effect on sleep duration at 250 mg/kg. The total flavonoid contents of solvent fractions were proportional to sleep duration. Like diazepam (a GABAA–benzodiazepine (BZD) receptor agonist), the hypnotic effects of GRPE, GOPE, and their EA fractions were fully inhibited by flumazenil (a GABAA–BZD receptor antagonist). These results suggest that potentiation effects of GRPE and GOPE on pentobarbital-induced sleep in mice may be modulated by a GABAergic mechanism.  相似文献   
49.
潘沛玲 《当代化工》2016,(8):1700-1703
比较了活性炭吸附法和改性柚子皮吸附法对废水中铅的去除能力。实验结果表明,活性炭吸附法对废水中铅的去除率为93.3%,耗时40 min;改性柚子皮吸附法对废水中铅的去除率为87.2%,耗时90 min。活性炭吸附法比改性柚子皮吸附法的耗时少,对废水中铅的去除率更高。但活性炭吸附法的处理成本比较高,利用改性后的柚子皮对重金属进行处理,可以变废为宝,具有环保和经济双重效益。  相似文献   
50.
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