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1.
Crude palm oil (CPO) is the richest natural source of carotenes that are destroyed in the conventional processing. There is a growing demand for nutritional products containing bioactive constituents externally fortified or preserved through modified process. A commercially viable process for the production of red palm olein (RPOn) rich in carotenes, tocols and sterols has been developed at pilot scale. The process developed involved neutralization of CPO followed by crystallization at controlled rate of cooling and deodorization of the resultant neutralized and winterized palm olein (WPOn) under controlled conditions of temperature and high vacuum. Analytical data related to micronutrients at each process step was monitored. The RPOn thus produced had not more than 0.25% of free fatty acids (FFA) and it retained more than 80% of the carotenes, about 85% of tocols and 65% of sterols originally present in the CPO. The physico-chemical characteristics of RPOn revealed that it is nutritionally of superior quality compared to that of the commercial refined bleached deodorized (RBD) palm olein currently available in the market. The carotenes, tocols and sterols profile of RPOn by HPLC showed that they were retained in their natural forms.  相似文献   
2.
An efficient pilot‐scale process was developed to produce nutraceutical products from fresh sea buckthorn (Hippophae rhamnoides) berries. Fresh berries were subjected to high‐pressure dewatering using a continuous screw press. The separated liquid phase containing 80–90% of pulp oil was clarified at 80 °C and centrifuged to obtain pulp oil, clear juice and sludge. The pulp oil yield was 2.7–2.8% of fresh berry weight with 66–70% extraction efficiency. The pulp oil was remarkably rich in carotenoids (2450–2810 mg kg?1), tocopherols (1409–1599 mg kg?1) and sterols (4096–4403 mg kg?1), with a characteristic fresh berry flavour and 16:1 as the major fatty acid (45.6–49.1%). The clear juice obtained was free from oil and contained high amounts of vitamin C (1683–1840 mg kg?1) and phytochemicals such as polyphenols (2392–2821 mg kg?1) and flavonoids (340–401 mg kg?1). Isorhamnetin (251–310 mg kg?1) was the major flavonoid in the juice, along with quercetin (77–81 mg kg?1) and kaempherol (12–16 mg kg?1). The juice was very acidic (pH 3), with high concentrations of organic acids (30.8–36.0 g kg?1). High‐performance liquid chromatography profiling of organic acids revealed quinic acid (18.1–19.9 g kg?1) as the major acid in the juice. The seeds in the pressed cake were separated and extracted for oil using supercritical CO2. Copyright © 2006 Society of Chemical Industry  相似文献   
3.
The oil content and chemical composition of the volatiles from whole capsule, decorticated seed and husk of four varieties of cardamom viz. Malabar, Mysore, Vazhukka, and Guatemala were studied. The differences in the aroma of cardamom from different sources were attributed to the ratio of esters and 1,8-cineole in the oil. The main constituents of the oils were found to be terpinylacetate and 1,8-cineol. The study revealed that the oil obtained from a whole capsule of the Malabar variety was superior in quality compared to the oil from other varieties. The in vitro total antioxidant capacity of the oils from whole capsules by two different methods was also carried out, and it was found that the Malabar variety has the highest antioxidant activity compared to other varieties.  相似文献   
4.
The pattern of accumulation of triacylglycerols, their fatty acid compositions and the positional distribution of the fatty acids at thesn-2- andsn-1,3-positions of the triacylglycerol molecules at progressive stages of oil palm fruit development were determined. There was an exponential rate of increase of triacylglycerols and their fatty acids toward the end of fruit development. The fatty acid composition of the triacylglycerols in the early stages of development, prior to active accumulation, was more or less similar, but differed appreciably from the later stages, and the transition of fatty acid composition toward that of normal palm oil occurred at around 16 wk after anthesis (WAA) and stabilized at 20 WAA. All fatty acids increased in terms of absolute quantity. There was an overall consistency in fatty acid positional distribution, irrespective of development stage. More saturated fatty acids were found to be esterified at thesn-1,3-positions and more unsaturated fatty acids at thesn-2-position of triacylglycerol. Higher rate of incorporation of 16:0 at the 1,3-positions during the active phase of triacylglycerol synthesis was observed, while 18:1 acid exhibited a reverse trend.  相似文献   
5.
Lipid classes and fatty acids were analyzed in expeller and rotary extracted coconut oils and corresponding solvent extracted cake oils. Triacylglycerols (84.0 to 93.1%); 1,2 diacylglycerols (1.5 to 5.1%); 1,3 diacylglycerols (1.2 to 2.1%); monoacylglycerols (1.0 to 7.0%); free fatty acids (1.0 to 2.6%); phospholipids (0.03 to 0.4%) and glycolipids (0.2 to 0.35%) were present in these oils. Fatty acid composition of triacylglycerols, phospholipids and glycolipids resembled each other and differed from those of 1,2 and 1,3 diacylglycerols which in turn were similar.  相似文献   
6.
The aim of this work is to implement simple edge isolation techniques in buried contact solar cell (BCSC) process by preserving the active cell area. Here we present results of two simplified edge isolation techniques for BCSC and they are compared with the standard process incorporating mechanical edge isolation using a dicing saw. The first technique is chemical wet etching of the solar cell's rear side in an inline system recently developed by University of Konstanz and Rena. The second technique is edge removal carried out in a fluoride/oxide radicals environment of a Asyntis plasma etcher. While the shunt resistance Rsh obtained with wet etching is between 1500 and 7000 Ω cm2, the standard process shows Rsh values ranging from 2100–6300 Ω cm2. The Rsh after plasma processing is between 1000 and 3600 Ω cm2. These cell results show that both wet and plasma etching achieve results close to mechanical edge isolation.However, a slight reduction of short circuit current is observed for the cells undergone standard as well as plasma processing. This is due to the presence of floating volume shunts formed at the rear n–p+ junction, which are not removed by either the standard or plasma process. These shunts do not influence the IV-curve of the solar cells and are nearly invisible with conventional thermography, as they are not connected to the front side emitter grid. Hence, light-modulated lock-in thermography measurements were carried out to analyse these shunts.  相似文献   
7.
Abstract: Interactions of phenolics with other food constituents and digestive enzymes are likely to have interference with the digestion and bioavailability of food and phenolics. In this study the effect of sea buckthorn proanthocyanidins on in vitro digestion of protein was evaluated. Optimization of the extraction conditions showed that maximum recovery of sea buckthorn proanthocyanidins was obtained with acidified acetone; water mixture (60% to 70%, v/v). Crude proanthocyanidin extracts thus prepared were purified using sephadex gel column chromatography and their average degree of polymerization and the effects on enzymatic hydrolysis of bovine serum albumin as influenced by their protein precipitation capacities were studied. Average degree of polymerization of proanthocyanidins in berry pulp, kernel, seed coat, and leaves was 7.4, 5.6, 8.2, and 10.6, respectively. The EC50 values for the protein precipitation by the PA of berry pulp, kernel seed coat, and leaves were 44.2, 44.1, 65.8, and 39.8 μg, respectively. Relative enzymatic hydrolysis of the protein‐proanthocyanidin complexes was 44.1% to 60.3% for pepsin and 57.5% to 67.7% for trypsin. Interactions of sea buckthorn proanthocyanidins with food proteins and digestive enzymes might alter the protein digestibility and phenolic bioavailabilty.  相似文献   
8.
Milk fats obtained from colostrum and early, middle and late lactation samples of buffalo milk were analyzed for their triacylglycerol (TG) compositions. Each milk fat first separated by thin layer chromatography (TLC) into high, medium and low molecular weight TG. The TG fractions thus obtained were further segregated by argentation TLC, according to their degree of unsaturation into saturated,trans-monoene,cis-monoene, diene and polyene species. With progressive lactation, the major changes from colostral fat were an increase in lower fatty acids and decline in oleic acid. This caused, in turn, marked variations in saturated TG and diene TG and, to a smaller extent, in polyene TG. Monoene TG, bothcis andtrans, remained practically constant throughout. These trends were largely reversed toward the end of lactation. NDRI publication no. 79-297.  相似文献   
9.
Syzygium cumini, widely known as Jamun, is a tropical tree that yields purple ovoid fleshy fruit. Its seed has traditionally been used in India for the treatment of diabetes. Based on the available ethno‐pharmacological knowledge, further studies were extended to understand the chemical composition and antioxidant activities of three anatomically distinct parts of fruit: the pulp, kernel and seed coat. Fruit parts, their corresponding ethanol extracts and residues were evaluated for chemical composition. The alcoholic extract was evaluated for its antioxidant potential against DPPH?, OH?, O2?? and lipid peroxidation. The whole fruit consisted of 666.0 ± 111.0 g kg?1 pulp, 290.0 ± 40.0 g kg?1 kernel and 50.0 ± 15.0 g kg?1 seed coat. Fresh pulp was rich in carbohydrates, protein and minerals. Total fatty matter was not significant in all three parts of fruit. Detailed mineral analysis showed calcium was abundant in all fruit parts and extracts. Total phenolics, anthocyanins and flavonoid contents of pulp were 3.9 ± 0.5, 1.34 ± 0.2 and 0.07 ± 0.04 g kg?1, respectively. Kernel and seed coat contained 9.0 ± 0.7 and 8.1 ± 0.8 g kg?1 total phenolics respectively. Jamun pulp ethanol extract (PEE), kernel ethanol extract (KEE) and seed coat ethanol extract (SCEE) showed a high degree of phenolic enrichment. DPPH radical scavenging activity of the samples and standards in descending order was: gallic acid > quercetin > Trolox > KEE > BHT > SCEE > PEE. Superoxide radical scavenging activity (IC50) of KEE was six times higher (85.0 ± 5.0 µg mL?1) compared to Trolox (540.0 ± 5.0 µg mL?1) and three times compared to catechin (296.0 ± 11.0 µg mL?1). Hydroxyl radical scavenging activity (IC50) of KEE was 151.0 ± 5.0 µg mL?1 which was comparable with catechin (188.0 ± 6.0 µg mL?1). Inhibition of lipid peroxidation of the extracts was also studied and their activity against peroxide radicals were lower than that of standard compounds (BHT, 79.0 ± 4.0 µg mL?1; quercetin, 166.0 ± 13.0 µg mL?1; Trolox, 175.0 ± 4.0 µg mL?1; PEE, 342.0 ± 17.0 µg mL?1; KEE, 202.0 ± 13.0 µg mL?1 and SCEE, 268.0 ± 13.0 µg mL?1. Copyright © 2007 Society of Chemical Industry  相似文献   
10.
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