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81.
BACKGROUND: Safflower (Carthamus tinctorius L.), usually grown as a source of oil crop, can be used as fodder either for hay or ensiling purposes, particularly in semi‐arid regions. RESULTS: A 2‐year trial was conducted in southern Italy to evaluate the production and forage quality of safflower biomass cv. Centennial, harvested at three different stages: 1, at complete appearance of primary buds (PB); 2, at complete appearance of secondary and tertiary buds (STB); and 3, at 25% of flowering stage (FS). For each stage of growth, 50% of the biomass was ensiled in 4 L glass jars without and with inoculation (Lactobacillus plantarum, LAB), and the other 50% was field wilted for 24 h before ensiling. Dry matter (DM) content and yield (DMY), pH, buffering capacity (BC) and water soluble carbohydrates (WSC) were determined on fresh forage. On safflower silages were also evaluated ammonia‐N, crude protein (CP), fibre fractions, fat, lactic and acetic acids, Ca and P, and gas losses. DMY ranged from 4.5 t ha?1 (PB harvesting) to 11.6 t ha?1 (FS harvesting). DM content varied from 129 g kg?1 (PB not wilted) to 630 g kg?1 (FS wilted). The WSC in forage before ensiling with not wilting ranged from 128 (PB stage) to 105 and 100 g kg?1 DM at STB and FS stages, respectively. The wilted safflower forage showed a lower WSC compared to wilted forage. The high sugar substrate allowed lactic acid fermentation and a good conservation quality in all the harvesting stages. Silages quality was strongly influenced by the treatment performed. Wilting practice increased DM, pH and NDF contents but reduced lactic acid, acetic acid and NH3‐N values. Inoculation reduced DM, pH and NDF contents, but increased lactic and acetic acids, CP and ash. CONCLUSION: As result, wilting the forage for 1 day was very effective in the early harvesting stage because this practice significantly increased DM, reducing on the same time the intensive fermentation and proteolysis processes of silage. When harvesting is performed at the beginning of the flowering stage wilting is not necessary. Copyright © 2011 Society of Chemical Industry  相似文献   
82.
BACKGROUND: Safflower, whose botanic name is Carthamus tinctorius L., is a member of the family Compositae or Asteraceae. Carthamus yellow (CY) is the main constituent of safflower and is composed of safflomin A and safflomin B. Dried safflower petals are used in folk medicine and have been shown to invigorate blood circulation, break up blood stasis, and promote menstruation. In addition, dried safflower petals contain yellow dyes that are used to color food and cosmetics. In this study, we investigated the effects of dried safflower petals aqueous extracts (SFA) and CY on lipopolysaccharide (LPS)‐induced inflammation using RAW264.7 macrophages. RESULTS: Our data showed that treatment with SFA (1–1000 µg mL?1) and CY (1–2000 µg mL?1) does not cause cytotoxicity in cells. SFA and CY inhibited LPS‐stimulated nitric oxide (NO), prostaglandin E2 (PGE2), and interleukin 1β (IL‐1β) release, through attenuation of inducible nitric oxide synthase (iNOS) and cyclooxygenase‐2 (COX‐2) protein expression. Further, SFA and CY suppressed the LPS‐induced phosphorylation of nuclear factor‐κB, which was associated with the inhibition of IκB‐α degradation. CONCLUSION: These results suggest that SFA and CY provide an anti‐inflammatory response through inhibiting the production of NO and PGE2 by the downregulation of iNOS and COX‐2 gene expression. Thus safflower petals have the potential to provide a therapeutic approach to inflammation‐associated disorders. Copyright © 2010 Society of Chemical Industry  相似文献   
83.
本研究对新疆红花蜜的主要成分进行分析。通过分析检测出新疆红花蜜的理化特征、营养成分和活性成分,结果表明新疆红花蜜中的多酚类和黄酮类活性成分含量高,且含有萜类活性成分,萜类成分首次在蜂蜜中检出。新疆红花蜜中的总酚含量均值为65.11 mg没食子酸/100 g蜂蜜,总黄酮含量均值为16.60 mg芦丁/100 g蜂蜜,萜类化合物含量均值为9.36 mg熊果酸/100 g蜂蜜。新疆红花蜜中的淀粉酶均值高达39.08 m L/(g·h),高于国家标准;主要微量元素有9种,呈现高钾(均值79.01 mg/100 g)、低钠(均值2.14 mg/100 g)、高钙(均值2.69 mg/100 g)的特征;维生素以V_C和B族维生素为主;氨基酸有18种,氨基酸总量均值为190 mg/100 g蜂蜜,其中脯氨酸含量高达44 mg/100 g蜂蜜,占氨基酸总量的23%。结论:新疆红花蜜的主要理化质量指标高、营养成分全面、丰富,活性功能成分种类多、含量高,具备优质蜂蜜的主要特点,并有望开发为特色蜂蜜及区域标志性蜂产品。   相似文献   
84.
Previous studies demonstrate humans can detect fatty acids via specialized sensors on the tongue, such as the CD36 receptor. Genetic variation at the common single nucleotide polymorphism rs1761667 of CD36 has been shown to differentially impact the perception of fatty acids, but comparative data among different ethnic groups are lacking. In a small cohort of Caucasian and East Asian young adults, we investigated if: (1) participants could detect oleic acid (C18:1) added to safflower oil emulsions at a constant ratio of 3% (w/v); (2) supplementation of oleic acid to safflower oil emulsions enhanced perception of fattiness and creaminess; and (3) variation at rs1761667 influenced oleic acid detection and fat taste perception. In a 3‐alternate forced choice test, 62% of participants detected 2.9 ± 0.7 mM oleic acid (or 0.08% w/v) in a 2.8% safflower oil emulsion. Supplementation of oleic acid did not enhance fattiness and creaminess perception for the cohort as a whole, though East Asians carrying the GG genotype perceived more overall fattiness and creaminess than their AA genotype counterparts (P < 0.001). No differences were observed for the Caucasians. These preliminary findings indicate that free oleic acid can be detected in an oil‐in‐water emulsion at concentrations found in commercial oils, but it does not increase fattiness or creaminess perception. Additionally, variation at rs1761667 may have ethnic‐specific effects on fat taste perception.  相似文献   
85.
Conjugated linoleic acid (CLA) refers to a mixture of conjugated octadecadienoic acids of predominantly ruminant origin. The main isomer in bovine milk fat is the cis-9, trans-11 CLA. Interest in CLA increased after the discovery of its health-promoting properties, including potent anticarcinogenic activity. Two experiments were conducted to evaluate dietary strategies aimed at increasing the concentration of CLA in bovine milk fat. Both experiments were organized as a randomized complete block design with a repeated measures treatment structure. In Experiment 1, 28 Holstein cows received either a control diet or one of 3 treatments for a period of 2 wk. The control diet consisted of 60% forage (barley silage, alfalfa silage, and alfalfa hay) and 40% concentrate on a dry matter (DM) basis, fed as a total mixed ration (TMR). The concentrate was partially replaced in the treatment groups with 24 ppm of monensin (MON), 6% of DM safflower oil (SAFF), or 6% of DM safflower oil plus 24 ppm of monensin (SAFF/M). Average cis-9, trans-11 CLA levels in milk fat after 2 wk of feeding were 0.45, 0.52, 3.36, and 5.15% of total fatty acids for control, MON, SAFF, and SAFF/M, respectively. In Experiment 2, 62 Holstein cows received either a control diet or one of 5 treatment diets for a period of 9 wk. The control diet consisted of 60% forage (barley silage, alfalfa silage, and alfalfa hay) and 40% concentrate on a DM basis, fed as a TMR. The concentrate was partially replaced in the treatment groups with 6% of DM safflower oil (SAFF), 6% of DM safflower oil plus 150 IU of vitamin E/kg of DM (SAFF/E), 6% of DM safflower oil plus 24 ppm of monensin (SAFF/M), 6% of DM safflower oil plus 24 ppm of monensin plus 150 IU of vitamin E/kg of DM (SAFF/ME), or 6% of DM flaxseed oil plus 150 IU of vitamin E/kg of DM (FLAX/E). Average cis-9, trans-11 CLA levels during the treatment period were 0.68, 4.12, 3.48, 4.55, 4.75, and 2.80% of total fatty acids for control, SAFF, SAFF/E, SAFF/M, SAFF/ME, and FLAX/E, respectively. The combination of safflower oil with monensin was particularly effective at increasing milk fat CLA. The addition of vitamin E to the diet partially prevented the depression in milk fat associated with oilseed feeding, but had no significant effect on the concentration of CLA in milk.  相似文献   
86.
Studies were conducted to investigate whether adsorption of amphiphiles from oil onto a degreased metal can be predicted from knowledge about adsorption of the amphiphiles at the oil-water interface. The surface of a degreased metal comprises oxides, hydroxides, and adsorbed water vapor, which form from the reaction of the metal with air and moisture. If the behaviors of amphiphiles at water-oil and metal-oil interfaces are similar, this information can be useful in the development of cheaper and quicker methods of estimating amphiphile adsorption properties on degreased metals. The amphiphiles used were safflower oil (SA) and jojoba oil (JO), both of which are plant-based oils, and methyl palmitate (MP). SA is a triester whereas JO and MP are monoesters. The interfacial tension of water-hexadecane was measured as a function of amphiphile concentration in hexadecane and used to estimate an interfacial-based free energy of adsorption, ΔG ads. The resulting interfacial-based ΔG ads values for SA were identical to those reported from friction-based adsorption isotherms. The corresponding values for the monoesters were within the range reported from friction-based adsorption isotherms.  相似文献   
87.
In this study, ultrasound-assisted (UA) neutralization parameters are optimized using the response surface methodology to develop a novel alkali neutralization method based on the minimal refining concept. Sodium hydroxide (NaOH), magnesium oxide (MgO), and calcium hydroxide (Ca(OH)2) are used in both the traditional (TR) and UA neutralizations. Optimum probe depth, duration, and intensity levels are calculated as 3.7 cm, 25 s, and 54.3%, respectively, for UA neutralization with NaOH, which is more successful at free fatty acid (FFA) reduction and total phenolic content (TPC) retention than MgO and Ca(OH)2. Validation results of optimum conditions show that lowest average FFA content (0.29%) and highest average TPC (211.2 mg kg−1) are determined for the UA-neutralized safflower oil samples. The comparison of all the neutralization experiments reveal that the UA neutralization under optimum conditions using NaOH reduced 82.8% of the FFA content, whereas the TR alkali neutralization reduced the FFA content at a maximum of only 47.8%. Practical Applications: From the results, it can be inferred that the UA neutralization exhibits good performance in FFA content reduction and bioactive compound retention while offering a good solution within the concept of minimal refining.  相似文献   
88.
红花油脂肪酸单甘酯的合成及其宏观动力学研究   总被引:3,自引:0,他引:3  
以新疆红花籽油和甘油为原料,在碱催化下合成红花油脂肪酸甘油单酯。用正交实验确定了合成反应的最佳参数:甘油/红花油的摩尔比为3:1,催化剂NaOH的用量为红花油质量的0.14%。在以上的优化参数条件下,当优化的反应温度为195℃,反应时问为80mim,可获得产率为62.54%。在2.5h的反应时间里,以红花油为关键组分研究了红花油甘油酯合成的宏观动力学模型。结果表明,红花油脂肪酸甘油酯合成反应表现为准一级反应,并得到了不同时间段内反应动力学方程。  相似文献   
89.
The gelation of the vegetable oils using fat crystals has gained significant attention in recent years. These formulations have been explored for food and pharmaceutical applications. The alteration in the properties of palmitic acid (20–40% w/w) and safflower oil oleogels is extensively studied at microscopic and macroscopic levels. The thermal and mechanical stability of the oleogels is improved when the proportion of the palmitic acid content is increased. However, under stress, the fat crystal network junction zones of the oleogels with higher proportions of palmitic acid undergo disruption. The changes in the properties of the oleogels are due to the alteration in the molecular packing, crystallite size, and lattice strain of the fat crystal network. The alteration in the properties is governed by the changes in the extent of inter‐ and intramolecular hydrogen bonding within the components of the oleogels. The oleogels can demonstrate the ability to deliver the drug, voriconazole, across the corneal tissue. Further, the prepared oleogels are biocompatible to murine fibroblast cells and do not elicit adverse reactions when instilled within the ocular sac of rabbits. The results suggest that the oleogels can be tried as ocular delivery vehicles. Practical Applications: The delivery of drug into the internal structure of the eye is a great challenge for the ophthalmologists. Usually no more than 1% of the drug can be delivered through conventional techniques. Various researchers have proposed the use of lipid‐based ocular drug delivery systems. Some of them include solid liquid nanoparticles, emulsions, and liposomes. However, the preparation of these formulations requires a tedious process. Keeping this in mind, it is proposed to synthesize oleogel as probable ocular drug delivery system.  相似文献   
90.
Response surface methodology is a statistical design that helps one to determine optimal conditions for an enzyme-catalyzed reaction by performing a minimal number of experiments. This methodology was adapted for modifying coconut oil TAG by using lipase-catalyzed acidolysis in hexane to incorporate n−3 or n−6 PUFA. FFA obtained after hydrolysis of cod liver oil and safflower oil were used as acyl donors. Immobilized lipase, Lipozyme IM60, from Rhizomucor miehei was used for catalyzing the reaction. The reaction conditions—substrate molar ratio, incubation time, and temperature—were optimized. The experimental data were fitted to a response function based on the central composite rotatable design. The optimal conditions generated from models indicated that maximal incorporation of n−3 PUFA occurred at a 1∶4 molar ratio of TAG/FFA when incubation was carried out for 34 h at 54°C. Similarly, maximal incorporation of n−6 FA was predicted at a 1∶3 molar ratio of TAG/FFA when incubated for 48.5 h at 39°C. Experiments conducted at optimized conditions predicted by the equation obtained from response surface methodology yielded structured lipids with 13.65 and 45.5% of n−3 and n−6 FA, respectively. These values agreed well with that predicted by the model. The reactions were also scaled up to 100 g levels in batch reactors with the incorporation level of n−3 and n−6 fatty acids agreeing closely with that observed when the reactions were carried out at lab scale (100 mg). These studies indicated that response surface methodology is a useful tool in predicting the conditions for incorporating desired levels of specific FA during the synthesis of structured lipids.  相似文献   
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