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1.
Chun Yang Yin Sharifah Aishah Syed Abdul KadirYing Pei Lim Sharifah Nawirah Syed-AriffinZurinawati Zamzuri 《Fuel Processing Technology》2008
Ash derived from combustion of Malaysian oil palm biomass (empty fruit bunches consisting of fibers) was physically and chemically characterized in order to provide a comprehensive understanding of its specific properties in terms of toxicity, compositions and reusability. Principal analyses conducted include particle size distribution, scanning electron microscopy, elemental dispersive X-ray, elemental analysis, toxicity characteristic leaching procedure (TCLP) as well as thermogravimetric, X-ray diffractometry and Fourier-transform infrared analyses. TCLP result indicated that the oil palm ash (OPA) should not be classified as toxic wastes in terms of heavy metal leachability since leachable copper, cadmium, lead and nickel concentrations were detected below the stipulated leachability limits. It was determined that the OPA contained high amount of potassium as well as presence of silica which implied its suitability to be reused as crude fertilizer or cement replacement material. 相似文献
2.
Sylvia V A Uzochukwu Esther Balogh Owen G Tucknot Mervyn J Lewis Patrick O Ngoddy 《Journal of the science of food and agriculture》1994,64(4):405-411
Palm wine and pasteurised palm sap volatiles were collected, concentrated on a Tenax GC and analysed by gas chromatography and gas chromatography-mass spectrometry. Eighty-two components were identified: 47 esters, 9 alcohols, 5 acids, 6 carbonyls, 2 acetals, 4 terpenes and 9 hydrocarbons. These had all been found previously in conventional wines. Odour evaluation of the separated palm wine components as they eluted suggested that no one compound is responsible for the characteristic palm wine odour. The acetates of higher alcohols and the ethyl esters of straight-chain aliphatic C6-C10 acids seemed to be important and may play a big role in imparting the fruity nuances of characteristic palm wine odour. Their association with alcohols seemed also to be necessary for the expression of typical palm wine odour. The qualitative difference between palm sap aroma and palm wine aroma appeared to be due mainly to the presence of these esters and alcohols in palm wine and their apparent absence from palm sap, as well as to the presence of some low-boiling esters and alcohols in palm sap and their apparent absence from palm wine. 相似文献
3.
Ibrahim M. Alarifi 《乙烯基与添加剂工艺杂志》2021,27(1):77-88
This study aims to examine the morphology and mechanical properties (tensile, flexural, and compressive) of epoxy composites reinforced with epoxy date palm leaves (EDPL), epoxy date palm branch (EDPB), and epoxy/hardener date palm core shell (EDPC) fibers (particle size <1 μm depend on the date palm fibers). A three-step technique was used to obtain the composites. The EDPL composites showed a maximum tensile strength of 3.45 MPa, while the EDPB composites showed maximum compressive and flexural rigidity of 9.46 and 5.55 MPa, respectively, owing to the good compatibility of fiber-matrix bonding. In this work, epoxy composites reinforced with date palm fibers (DPF) leaves, branches, and core shell were recycled using a cost-effective and easily reproducible three-step technique. EDPC fibers fabricated with 64.65% weight carbon fibers content demonstrated improved tensile strengths and stiffness properties. The three samples of palm date composites revealed mechanical properties that could be used to trial these fibers for manufacturing purposes, and to exploit their extraordinary mechanical properties shown in current results. 相似文献
4.
Shi-Cheng Tong Teck-Kim Tang Yee-Ying Lee 《European Journal of Lipid Science and Technology》2021,123(12):2100132
Fractionation is a well-established process adopted in the fats and oils industries. It involves the separation of low and high melting triacylglycerol under controlled cooling conditions into olein and stearin fractions with distinct chemical and physical properties. Amongst the other vegetable oils, palm oil is one of the most fractionated oils in the past few decades mainly attributed to its semisolid properties. The various fraction of palm oil allows it to be used in different types of food products such as margarine, frying oil, and cocoa butter substitute. In fractionation, proper control of the fractionation conditions is important to produce the fractions with desirable stearin and olein quality. The purpose of this paper is to critically review the fractionation conditions (crystallization temperature, agitation, cooling rate and crystallization time) that affect the yield and quality of the oil produced. Additionally, it also provides the latest updates on the influence of seeding agents (diacylglycerol, monoacylglycerol, hard fat, phytosterol, phospholipid, lecithin, essential oil, sugar, polyglycerol ester, and talc) used in fractionation. This article is useful to provide a fundamental understanding of fractionation to scientists from the industries or academia working in the fats and oils industries. Practical Applications: This paper provides an in-depth understanding of fractionation particularly on the parameters of fractionation in influencing the quality and yield of the stearin and olein produced. It also for the first time presents the effect of addition of various seeding agents on palm oil fractionation which can help the industry to select the appropriate seeding agents to improve the currently employed fractionation process. Thus, it can act as a guideline for the industry to understand and select the appropriate fractionation conditions when developing a new product using this approach. The fractionation conditions discussed here can also be used as a reference when fractionating other types of fats and oils as most of them share a common background. 相似文献
5.
Paresh Chandra Dutta 《Journal of the American Oil Chemists' Society》1997,74(6):659-666
Hydrogenated rapeseed oil/palm oil blend, sunflower oil and high-oleic sunflower oil, and French fries fried in these oils
were assessed for contents of sterol oxidation products. Different oxidation products of phytosterols (7α- and 7β-hydroxy-sito-and
campesterol, 7-ketosito- and 7-ketocampesterol, 5α,6α-epoxy-sito- and campesterol, 5β,6β-epoxy-sito-and campesterol, dihydroxysitosterol
and dihydroxycampesterol) were identified and quantiated by gas chromatography (GC) and GC-mass spectroscopy. Rapeseed oil/palm
oil blend contained 41 ppm total sterol oxides before frying operations. After two days of frying, this level was increased
to 60 ppm. Sunflower oil and high-oleic sunflower oil had 40 and 46 ppm sterol oxides, respectively, before frying operations.
After two days of frying operations, these levels increased to 57 and 56 ppm, respectively. In addition to campesterol and
sitosterol oxidation products, small amounts of 7α- and 7β-hydroxystigmasterol were detected in the oil samples. Total sterol
oxides in the lipids of French fries fried at 200°C in rapeseed oil/palm oil blend, sunflower oil, and high-oleic sunflower
oil were 32, 37, and 54 ppm, respectively. The levels of total oxidized sterols, calculated per g sample, ranged from 2.4
to 4.0 ppm. In addition to the content of phytosterol oxides, full scan mass spectra of several oxidation products of stigmasterol
are reported for the first time.
Part of these results were presented at the 86th Annual Meeting of the AOCS, May 7–11, 1995, San Antonio, TX. 相似文献
6.
L. deMan V. D’Souza J. M. deMan B. Blackman 《Journal of the American Oil Chemists' Society》1992,69(3):246-250
A number of North American vegetable and animal fat shortenings, which had been analyzed previously for their physical and
textural characteristics, were analyzed also for their chemical composition. The fatty acid and triglyceride composition of
the solids were calculated by analyzing the composition of the original product and the liquid phase, and by determination
of the solid fat content (SFC) of the fat. The solids were also isolated by isopropanol (IP) separation, and the high melting
glycerides (HMG) by acetone crystallization at 15°C. There was not much difference in total saturates andtrans content between vegetable and animal fat shortenings. Changing formulations from soy-palm to soy-cottonseed does not change
the total saturates plustrans content. The solids of the vegetable shortenings in the β form contained about 20% of 16:0, those in the β′ form 30% or more.
The animal fat shortenings were mainly in the β form, their solids contained 30% or more of 16:0. C54 triglyceride content
of the solids of β vegetable shortenings (calculated and IP-separated) was >45%, that of all animal fats was <25%. Solids
of animal fat shortenings contain high levels of C52. The C54 triglycerides are β-tending and should be kept low in vegetable
shortening. In the HMG the C54 should not exceed 30%. This can only be achieved by incorporation of a β′ hard fat, preferably
palm hard fat. Animal fat, especially lard, crystallizes in the β form because the palmitic acid in the glyceride molecule
is located in the 2-position, whereas those of vegetable fats are in the 1- and 3-position. 相似文献
7.
A rapid test to measure performance,emission and wear of a diesel engine fueled with palm oil diesel
H. Masjuki A. M. Zaki S. M. Sapuan 《Journal of the American Oil Chemists' Society》1993,70(10):1021-1025
Results of performance, emission and tribological evaluations of palm oil methyl ester and its blends with conventional diesel
in an automobile diesel engine test bed are presented. Polymerization and carbon deposits on the fuel injector were monitored.
CO, CO2, O2, combustion efficiency and temperature of exhaust gases were also measured. Palm oil methyl ester and its blends have great
potential as alternative diesel fuel. Performance and exhaust gas emission for palm oil methyl ester and its blends with conventional
diesel are comparable with those of conventional diesel fuel. Palm oil methyl ester does not pose a severe environmental problem
and will not deteriorate engine and bearing components. 相似文献
8.
Sirirung Wongsakul Poonsuk Prasertsan Uwe T. Bornscheuer Aran H‐Kittikun 《European Journal of Lipid Science and Technology》2003,105(2):68-73
Commercial immobilized lipases were used for the synthesis of 2‐monoglycerides (2‐MG) by alcoholysis of palm and tuna oils with ethanol in organic solvents. Several parameters were studied, i.e., the type of immobilized lipases, water activity, type of solvents and temperatures. The optimum conditions for alcoholysis of tuna oil were at a water activity of 0.43 and a temperature of 60 °C in methyl‐tert‐butyl ether for ~12 h. Although immobilized lipase preparations from Pseudomonas sp. and Candida antarctica fraction B are not 1, 3‐regiospecific enzymes, they were considered to be more suitable for the production of 2‐MG by the alcoholysis of tuna oil than the 1, 3‐regiospecific lipases (Lipozyme RM IM from Rhizomucor miehei and lipase D from Rhizopus delemar). With Pseudomonas sp. lipase a yield of up to 81% 2‐MG containing 80% PUFA (poly‐unsaturated fatty acids) from tuna oil was achieved. The optimum conditions for alcoholysis of palm oil were similar as these of tuna oil alcoholysis. However, lipase D immobilized on Accurel EP100 was used as catalyst at 40 °C with shorter reaction times (<12 h). This lead to a yield of ~60% 2‐MG containing 55.0‐55.7% oleic acid and 18.7‐21.0% linoleic acid. 相似文献
9.
Hiromi Yoshida Mikiko Tatsumi Goro Kajimoto 《Journal of the American Oil Chemists' Society》1991,68(8):566-570
Effects of microwave heating on the oxidative stability ofd-tocopherols were studied in relation to the production of fatty acids in oils. During microwave heating, the stability of
tocopherols decreased in the orderδ>β>γ>α. This order did not depend on the types of ethyl esters of fatty acids or oils present. But, the shorter the chainlength
and the lower the degree of unsaturation of the fatty acid ethyl esters, the greater was the reduction in amount of individual
tocopherols. A similar tendency was observed when tocopherol-stripped vegetable oils, with equimolar mixtures of tocopherols
added, were treated under the same conditions. The reduction in tocopherols became greater with increasing levels of free
fatty acids. 相似文献
10.
P.?N.?Mayamol T.?Samuel C.?Balachandran A.?Sundaresan C.?ArumughanEmail author 《Journal of the American Oil Chemists' Society》2004,81(4):407-413
Several pilot-scale trials reported in this paper, using palm stearin-rice bran oil (PS-RBO) blends, obviously did not contain
trans FA (TFA), whereas the commercial products were found to contain 18–27% TFA. The effects of processing conditions such as
rate of agitation, crystallization temperature, and composition of the blends on the crystal structure of shortenings were
studied. The products were evaluated for their physicochemical characteristics using DSC, X-ray diffraction (XRD), HPLC, and
FTIR techniques. The formulation containing 50% PS and 50% RBO showed melting and cooling characteristics similar to those
of hydrogenated commercial “vanaspati” samples. Analysis of the FA composition revealed that the formulated shortenings contained
15–19% C18∶2 PUFA. Tocopherol and tocotrienol contents of the experimental shortenings were in the range of 850–1000 ppm with oryzanol
content up to 0.6%. XRD studies demonstrated that the crystal form in the shortenings was predominantly the most stable β′
form, and there was less of the undesirable β form. 相似文献