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201.
Kenneth D. Carlson Robert Kleiman Robert P. Pavlik 《Journal of the American Oil Chemists' Society》1993,70(12):1269-1272
Simulation of commercial processing of Cuphea seed to obtain needed quantities of oil and meal was accomplished with pilot
facilities. Cuphea seed was conditioned in a single-deck cooker. Cooked seed was pressed with a mechanical screw with two-speed
shaft, variable-speed drives and a four-section cage with cored sleeves. A feed rate of 22 kg seed/h and a feed screw-to-main
shaft ratio of 2:1 gave good press cake with 8.1% residual oil. Press cake was extracted in a batch-type modular extraction
pilot plant. Miscella stages were sequentially pumped through the beds, followed by hexane rinses. Spent cake was desolventized
and toasted, and full miscellas were stripped to recover the crude oil. The finished Cuphea meal had only 0.30–0.55% residual
oil. Thus, conditioned Cuphea seed was easily pressed without prior flaking to acceptable cakes, and conditions simulating
commercial solvent extraction efficiently removed residual cake oil. 相似文献
202.
Ortiz-Gonzalez G Jimenez-Flores R Bremmer DR Clark JH DePeters EJ Schmidt SJ Drackley JK 《Journal of dairy science》2007,90(11):5018-5031
Modification of milk fat composition might be desirable to alter manufacturing characteristics or produce low saturated fat dairy products that more closely meet consumer dietary preferences. The aim of this research was to evaluate functional properties of butter oil obtained from milks with fat composition modified by altering the profile of long-chain fatty acids (FA) absorbed from the small intestine of cows. A control and 5 mixtures of long-chain free FA were infused into the abomasum of lactating dairy cows in a 6 × 6 Latin square design with 21-d periods. Treatments were 1) control (no FA infused), 2) mostly saturated FA (C16:C18 = 0.72), 3) low-linoleic palm FA (C16:C18 = 0.85), 4) palm FA (C16:C18 = 0.72), 5) soy FA (C16:C18 = 0.10), and 6) high-palmitic soy FA (C16:C18 = 0.68). All treatments included meat solubles and Tween 80 as emulsifiers. Solid fat content (from 0 to 40°C), melting point, and force at fracture were determined in butter oil. Milk fat from cows infused with palm FA (treatment 4) exhibited functionality equal to or better than control butter oil. Infusion with palm FA increased amounts of triglyceride (TG) fractions with 48, 52, and 54 carbon numbers but decreased TG with 32, 34, 36, and 42 carbon numbers. Infusion with soy FA increased TG with 26, 38, 40, 52, and 54 carbon numbers but decreased TG with 34, 42, and 46 carbons. Infusion of the mostly saturated FA increased TG with 38, 50, 52, and 54 carbon numbers but decreased TG with 32, 34, and 42 carbon numbers. These TG groups were consistently correlated with functional properties of butter oils from different treatments. The content of palmitic acid is important for maintaining functionality in the presence of increased polyunsaturated FA. The composition of milk fat may be able to be optimized through nutritional manipulation of diets for dairy cows if the optimal composition of FA and TG is defined for a particular dairy product. 相似文献
203.
Joan Citoler Dr. William Finnigan Dr. Han Bevinakatti Prof. Nicholas J. Turner 《Chembiochem : a European journal of chemical biology》2022,23(2):e202100578
Fatty amines represent an important class of commodity chemicals which have broad applicability in different industries. The synthesis of fatty amines starts from renewable sources such as vegetable oils or animal fats, but the process has multiple drawbacks that compromise the overall effectiveness and efficiency of the synthesis. Herein, we report a proof-of-concept biocatalytic alternative towards the synthesis of primary fatty amines from renewable triglycerides and oils. By coupling a lipase with a carboxylic acid reductase (CAR) and a transaminase (TA), we have accomplished the direct synthesis of multiple medium and long chain primary fatty amines in one pot with analytical yields as high as 97 %. We have also performed a 75 mL preparative scale reaction for the synthesis of laurylamine from trilaurin, obtaining 73 % isolated yield. 相似文献
204.
Ive Hermans Kris Janssen Bart Moens An Philippaerts Boris Van Berlo Jozef Peeters PierreA. Jacobs BertF. Sels 《Advanced Synthesis \u0026amp; Catalysis》2007,349(10):1604-1608
Herein we report a new, one‐step procedure for the metal‐free ketonization of unsaturated fatty acid methyl esters and triacylglycerol mixtures with nitrous oxide (N2O). The conversion of various substrates can be tuned by parameters such as temperature, reaction time and N2O partial pressure. This ketonization chemistry offers various advantages over the classic Wacker catalytic process and a state‐of‐the‐art two‐step procedure via intermediate epoxides. 相似文献
205.
Rheology of vegetable oil analogs and triglycerides 总被引:10,自引:6,他引:4
The rheological properties of two complex mixtures of short-chain triglycerides were experimentally determined. Dynamic or
absolute viscosities of the mixtures were measured for shear rates of 0.32 to 64.69 s−1 at temperatures between 25 and 80°C. The compositions of the mixtures were based on the oil of the plant species Cuphea viscosissima VS-320, a natural source of short-chain triglycerides. The dynamic viscosities of these mixtures were compared to those of
a traditional vegetable oil (peanut oil) and diesel fuel. The results of this comparison were used to make estimates of the
performance of such triglyceride mixtures as diesel fuel substitutes, since viscosity can be a key indicator of fuel performance
for possible substitute diesel fuels. The crystallization temperatures of these two mixtures were also determined experimentally,
and the effects of crystallization on fuel performance were projected. Additionally, the dynamic viscosities of pure triglycerides
from C6∶0 to C18∶0 at 75°C were plotted vs. chain length. These viscosities were measured at high shear rates (>6 s−1) where dynamic viscosity is shear-independent. An obvious trend in the relationship between triglyceride chain length and
viscosity was observed. A second-order regression was used to obtain an equation for this relationship. This equation was
used as a model for composition dependence of viscosity. This model was applied to the viscosities of the triglyceride mixtures
examined here. There was good agreement between the model and the actual, measured viscosity values determined in this study. 相似文献
206.
Enzymatic glycerolysis of soybean oil 总被引:1,自引:0,他引:1
Enzymatic glycerolysis of soybean oil was studied. Of the nine lipases that were tested in the initial screening, Pseudomonas sp. resulted in the highest yield of monoglycerides. Lipase from Pseudomonas sp. was further studied for the influence of temperature, thermal stability, enzyme/oil ratio, and glycerol/oil ratio. A
full factorial optimization approach was performed. The following conditions were tested over the specified ranges: temperature
(30–70°C), thermal stability (30–70°C), enzyme/oil ratio (0.05–0.2 g enzyme/10 g oil), glycerol/oil ratio (1:1–3:1 glycerol/oil
molar ratio) and 1 h reaction time. The stability of the enzyme at the reaction temperature was also incorporated as a separate
variable. At temperatures above 40°C enzyme denaturation offset the higher activity. The optimal conditions were selected
to be the basis for a continuous process: 40°C, a glycerol/oil molar ratio of 2:1, and an enzyme/oil ratio of 0.1 g enzyme/10
g oil. A definition for glycerolysis activity was adopted. The glycerolysis activity (1 GU) was defined as the amount of enzyme
necessary to consume 1 μmol of substrate (glycerol and oil) per minute. This research is intended to explore the reaction
parameters that are important in a continuous enzymatic glycerolysis process. 相似文献
207.
Djaafar Rehrah Mohamed Ahmedna Jianmei Yu Ipek Goktepe Steven Hurley Tracy Hanner Anuradha Rao‐Patel 《Journal of the science of food and agriculture》2007,87(7):1323-1329
‘The Vert’ is a special type of green tea widely consumed in West Africa and locally associated with many health benefits. However, limited research has been conducted to evaluate its health benefits, such as its enhanced hypolipidemic potential. The objectives of this study were to (1) evaluate the cholesterol‐ and triglyceride‐lowering effects of West African green tea (WAGT) as affected by diet and tea intake, (2) determine the impact of WAGT consumption on the CHD risk ratio, and (3) explore possible mechanisms through which WAGT improves serum lipid profile. Forty‐five male Wistar rats were randomly assigned to one of nine treatment combinations, three diets (regular, high‐cholesterol, and trans‐fat diets) and three fluid sources (no tea, diluted tea, and concentrated tea). After 6 weeks of feeding, animal blood, liver, and feces were harvested. Total cholesterol, HDLc, LDLc, and triglycerides in serum, liver, and feces were determined. The concentrations of bile acids in feces were also measured. WAGT significantly lowered serum and liver cholesterol (30% and 15%, respectively) and increased serum HDL cholesterol (30%). It also reduced liver enlargement caused by storage of excess lipids in high‐cholesterol diet. Overall, the CHD risk ratio was cut by two‐thirds in rats fed high‐cholesterol diet and WAGT. A marked increase in fecal total lipids, cholesterol (60%), and bile acids (50%) was observed in rats that consumed WAGT compared to the control group. These beneficial effects could be attributed to the significantly high flavonoid content of WAGT. Copyright © 2007 Society of Chemical Industry 相似文献
208.
The seeds of cultivated Hibiscus spp. were extracted with supercritical carbon dioxide, and the resulting extracts were analyzed to identify the major TG
components as the corresponding FAME. The seed oils were composed predominantly of oleic and linoleic FA (69.6–83.4%) with
lesser amounts of palmitic acid (14.8–27.0%). Minor amounts of C14, C18, and C20 saturated FA were also detected. The oil
content of the seeds was determined to be between 11.8 and 22.1 wt% for hybrid varieties and between 8.9 and 29.5 wt% for
the native species from which the hybrid varieties were developed. The protein content of the defatted seed meal averaged
20% for the hybrid varieties. The composition of the extracted hibiscus seed oils suggests potential edible applications. 相似文献
209.
Nor Aini Idris Leny deMan T. S. Tang C. L. Chong 《Journal of the American Oil Chemists' Society》1996,73(8):995-1001
Seven samples of domestic and imported Malaysian tub margarines were analyzed for their fatty acid and triglyceride (carbon
number) composition, solid fat content, dropping and softening points, crystallization temperature, polymorphic form, color,
and textural attributes. Domestic margarines were formulated from palm oil or palm olein and palm kernel oil with a liquid
oil but no hydrogenated oils. Two imported products contained hydrogenated palm oil product, which resulted in a high level
of β′ crystals, whereas the domestic nonhydrogenated products contained more β than β′ crystals. Crystal habit was related
to the fatty acid and triglyceride composition of the high-melting glycerides. Domestic products were firmer in texture, probably
because they were formulated to be sold in a tropical climate. 相似文献
210.
T. Reynolds J. V. Dring C. Hughes 《Journal of the American Oil Chemists' Society》1991,68(12):976-977
A white crystalline material isolated from the seeds ofUmbellularia californica consisted mainly of the mixed triglyceride, dilaurocaprin, with smaller amounts of trilaurin and dicaprolaurin and a trace
of tricaprin. The yield of crude oil from a tree growing at Royal Botanic Gardens, Kew, was considerably less than that reported
previously for trees growing in California. 相似文献