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排序方式: 共有111条查询结果,搜索用时 31 毫秒
1.
Mat Rasol Awang Hassan Hamdani Mutaat Mohd. Shukri Mahmud Wan Badrin Wan Husain Tajuddin Osman Khomsaton Abu Bakar Asmahwati Kassim Zal U''yun Wan Mahmud Ishak ManafTamikazu Kume Shoji Hashimoto 《Radiation Physics and Chemistry》1993,42(4-6):611-616
In solid state fermentation, Pleurotus sajor-caju has been found to be able to degrade at least 30% oil palm empty Fruit Bunch (EFB) fibre leaving 70 % useful materials. Conditions under which fermentation carried out were investigated. It was found that, in the temperature range between 25– 28 °C, relative ph between 6–8, moisture between 60–70 % and medium composition of CaCO3: rice bran 2 %: 5 % were the optimum conditions. The results showed in fermented products that, there were substantial reduction in cellulosic component such as Crude Fiber (CF, 18 %); Acid Detergent Fibre (ADF, 45 %), Neutral Detergent Fibre (NDF, 61 %) and Acid Detergent Lignin (ADL, 14 %). However, Crude Protein (CP, 10%) increased resulted from single cell protein enrichment of mycelial microbial mass. The mass reductions of substrate in fermentation process corresponds to the CO2 released during fermentation. Hence, attributable to the decreased in content of CF, ADF, NDF, and ADL. The digestibility study has also been carried out to determine the useful level of this product to ruminant. Aflatoxin content was detected low in both the initial substrates and products. Based on nutritional value and low content of aflatoxin, the product is useful as a source of roughage to ruminant. 相似文献
2.
We have developed conformational preference functions and a hierarchy of algorithms that can evaluate the success of each hydrophobicity scale in predicting protein secondary conformation. The results of such evaluation are shown for fiftyfive different scales with respect to their ability to predict -helix, -sheet and coil structure in three testing sets of proteins: five integral membrane proteins, twelve -class and sixteen -class soluble proteins. Our scale of conformational parameters is the best predictor of secondary structure segments in membrane proteins and -class proteins. The success rate and correlation coefficient for -helix conformation in membrane proteins are 76% and 0.46 respectively, which is superior to the performance measures attained with other prediction schemes. Evaluation of solution hydrophobicity scales, often used to predict transmembrane segments in membrane proteins, indicated absence of correlation in prediction of helix segments and experimental results for the conformation of membrane proteins. Such scales have better performance (correlation coefficient around 0.30) in predicting sheet conformation in the -class proteins. 相似文献
3.
Jens Hartig Andreas Schnepf L. Jos de Jongh David Bono Hansgeorg Schnöckel Prof. Dr. 《无机化学与普通化学杂志》2007,633(1):63-76
Towards the Understanding of the Unexpected Properties of the Metalloid Cluster Compound [Ga84(N(SiMe3)2)20][Li6Br2(THF)20]·2Toluol In several short communications we have recently reported on the electrical and superconducting properties of the crystalline title compound 1 which contains anionic Ga84R20‐moieties. Here we present a collection of these results, complemented and interpreted by using DFT‐calculations on model clusters (Ga84(NH2)20?). These calculations allow a) a first insight into the dynamics of the Ga84‐moieties (e.g. a rotation of the central Ga2‐dumbbell) and thus an explanation of the temperature‐dependent Ga‐NMR‐spectra described recently, and b) estimations on the lattice energy of 1 and its resulting unexpected energetic stabilization compared to metallic gallium. A possible contribution of the cations in the electrical conduction mechanism of 1 can also be made feasible with model calculations. The basis for all the results presented is to be found in the “perfect” arrangement of nanoscopic Ga84‐clusters in the crystal. This theoretically predicted condition for superconductivity in a “chain” of identical metal cluster molecules is a requirement which can hardly be realized by means of physical fabrication methods. Therefore, on the one hand the results presented here make for some disillusionment in the field of nanoscience, but on the other hand, especially in the field of synthetic chemistry, they present rewarding challenges for fundamental work in the future. 相似文献
4.
Yun Khoon Liew Vasanthakumari Neela Rukman Awang Hamat Syafinaz Amin Nordin Pei Pei Chong 《Electrophoresis》2013,34(3):397-400
The typical concentration of protein loaded varies from 0.13 to 1.40 μg/μL for a classical silver staining method in 2DE gel. Here, we present a simple modified classical silver staining method by modifying the silver impregnation and development reaction steps. This modified method detects the protein spots at extremely low loaded concentrations, ranging from 0.0048 to 0.0480 μg/μL. We recommend this modified silver staining as an excellent method for the limited biological samples used for silver‐stained 2DE analysis. Altogether, the protocol takes close to two days from first dimension separation to second dimension separation, followed by silver staining, scanning, and analysis. 相似文献
5.
Granular hydrogels are composed of hydrogel-based microparticles, so-called microgels, that are densely packed to form an ink that can be 3D printed, injected or cast into macroscopic structures. They are frequently used as tissue engineering scaffolds because microgels can be made biocompatible and the porosity of the granular hydrogels enables a fast exchange of reagents, waste products, and if properly designed even the infiltration of cells. Most of these granular hydrogels can be shaped into appropriate macroscopic structures, yet, these structures are mechanically rather weak. The poor mechanical properties prevent the use of these structures as load-bearing materials and hence, limit their field of applications. The mechanical properties of granular hydrogels depend on the composition of microgels and the interparticle interactions. In this review, we discuss different strategies to assemble microparticles into granular hydrogels and highlight the influence of inter-particle connections on the stiffness and toughness of the resulting materials. Mechanically strong and tough granular hydrogels have the potential to open up new fields of their use and thereby to contribute to fast advances in these fields. In particular, we envisage them to be well-suited as soft actuators and robots, tissue replacements, and adaptive sensors.The mechanical properties of granular hydrogels are strongly influenced by interparticle interactions. In this review, we compare the storage, compressive and tensile moduli of granular hydrogels cured using various interparticle interactions. 相似文献
6.
Soon-Lim ChongKhalijah Awang Marie Therese MartinMat Ropi Mokhtar Gomathi ChanMarc Litaudon Francoise GueritteKhalit Mohamad 《Tetrahedron letters》2012,53(40):5355-5359
Two structurally interesting novel limonoids, malayanine A and malayanine B, were isolated from the bark of Chisocheton erythrocarpus Hiern. The structures were fully characterized through spectroscopic methods. 相似文献
7.
A novel proaporphine-tryptamine dimer alkaloid, named phoebegrandine C 1, was isolated from the leaves of Phoebe grandis (Nees) Merr. Its structural elucidation was carried out using spectroscopic techniques, notably 2D NMR. 相似文献
8.
Ann M. Anderson Mary K. Carroll Emily C. Green Jason T. Melville Michael S. Bono 《Journal of Sol-Gel Science and Technology》2010,53(2):199-207
Hydrophobic silica aerogels have been prepared using the rapid supercritical extraction (RSCE) technique. The RSCE technique
is a one-step methanol supercritical extraction method for producing aerogel monoliths in 3 to 8 h. Standard aerogels were
prepared from a tetramethoxysilane (TMOS) recipe with a molar ratio of TMOS:MeOH:H2O:NH4OH of 1.0:12.0:4.0:7.4 × 10−3. Hydrophobic aerogels were prepared using the same recipe except the TMOS was replaced with a mixture of TMOS and one of
the following organosilane co-precursors: methytrimethoxysilane (MTMS), ethyltrimethoxysilane (ETMS), or propyltrimeth-oxysilane
(PTMS). Results show that, by increasing the amount of catalyst and increasing gelation time, monolithic aerogels can be prepared
out of volume mixtures including up to 75% MTMS, 50% ETMS or 50% PTMS in 7.5–15 h. As the amount of co-precursor is increased
the aerogels become more hydrophobic (sessile tests with water droplets yield contact angles up to 155°) and less transparent
(transmission through a 12.2-mm thick sample decreases from 83 to 50% at 800 nm). The skeletal and bulk density decrease and
the surface area increases (550–760 m2/g) when TMOS is substituted with increasing amounts of MTMS. The amount of co-precursor does not affect the thermal conductivity.
SEM imaging shows significant differences in the nanostructure for the most hydrophobic surfaces. 相似文献
9.
Kee CH Ariffin A Awang K Takeya K Morita H Hussain SI Chan KM Wood PJ Threadgill MD Lim CG Ng S Weber JF Thomas NF 《Organic & biomolecular chemistry》2010,8(24):5646-5660
The syntheses of fourteen unusual o-carboxamido stilbenes by the Heck protocol revealed surprising complexity related to intriguing substituent effects with mechanistic implications. The unexpected cytotoxic and chemopreventive properties also seem to be substituent dependent. For example, although stilbene 15d (with a 4-methoxy substituent) showed cytotoxicity on HT29 colon cancer cells with an IC(50) of 4.9 μM, the 3,4-dimethoxy derivative (15c) is inactive. It is interesting to observe that the 3,5-dimethoxy derivative (15e) showed remarkable chemopreventive activity in WRL-68 fetal hepatocytes, surpassing the gold standard, resveratrol. The resveratrol concentration needed to be 5 times higher than that of 15e to produce comparable elevation of NQO1. 相似文献
10.
A. A. Latif H. Ahmad N. A. Awang M. Z. Zulkifli C. H. Pua Z. A. Ghani S. W. Harun 《Laser Physics》2011,21(4):712-717
In this paper, a design of a High Power Tunable Fiber Laser (HP-TFL) in C-band region from 1536.7 to 1548.6 nm is set forth
with Erbium Doped Fibers (EDFs) being used as a seeding signal and a booster amplifier. With a 1 × 16 channels Arrayed Waveguide
Grating (AWG), this setup is capable of generating 16 different wavelengths with an average output power of 20.7 dBm. 相似文献