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71.
72.
Role of energy irradiation in aiding pretreatment of lignocellulosic biomass for improving reducing sugar recovery 总被引:1,自引:0,他引:1
Yu-Loong Loow Ta Yeong Wu Ge Hoa Yang Jamaliah Md. Jahim Wen Hui Teoh Abdul Wahab Mohammad 《Cellulose (London, England)》2016,23(5):2761-2789
With the depletion of crude oil reserves, the ever-increasing global energy consumption encourages the efforts to find alternative renewable sources for production of biofuels and value-added chemicals. The conversions of lignocellulosic biomass into biofuels and commodity chemicals via the biotechnological pathway have been the recent trend. Specifically, these products can be obtained through fermentation of reducing sugars, which are the main but basic derivatives from the biomass. In order to overcome the recalcitrant structure of the biomass for effective reducing sugar recovery, a pretreatment stage is normally required. Currently, one of the most novel forms of biomass pretreatment is using energy irradiation methods such as electron beam, gamma ray, pulsed electrical field, microwave and ultrasound. In general, these technologies are often used together with other more conventional chemical and/or biological pretreatment techniques for enhancing sugar recovery. Nevertheless, energy irradiation offers significant improvement in terms of possible cost reduction opportunities and reduced toxicity. Hence, this review highlights the recent studies of using energy irradiation for pretreating biomass as well as the industrial applications of reducing sugars in biotechnological, chemical and fuel sectors. In short, more research needs to be done at the scientific, engineering and economic levels to make energy irradiation one of the front runners in the field of biomass pretreatment. 相似文献
73.
Nellysha Namela Muhammad Abdul Kadar Fairus Ahmad Seong Lin Teoh Mohamad Fairuz Yahaya 《Molecules (Basel, Switzerland)》2021,26(18)
Metabolic syndrome (MetS) is a constellation of risk factors that may lead to a more sinister disease. Raised blood pressure, dyslipidemia in the form of elevated triglycerides and lowered high-density lipoprotein cholesterol, raised fasting glucose, and central obesity are the risk factors that could lead to full-blown diabetes, heart disease, and many others. With increasing sedentary lifestyles, coupled with the current COVID-19 pandemic, the numbers of people affected with MetS will be expected to grow in the coming years. While keeping these factors checked with the polypharmacy available currently, there is no single strategy that can halt or minimize the effect of MetS to patients. This opens the door for a more natural way of controlling the disease. Caffeic acid (CA) is a phytonutrient belonging to the flavonoids that can be found in abundance in plants, fruits, and vegetables. CA possesses a wide range of beneficial properties from antioxidant, immunomodulatory, antimicrobial, neuroprotective, antianxiolytic, antiproliferative, and anti-inflammatory activities. This review discusses the current discovery of the effect of CA against MetS. 相似文献
74.
Yip Foo Win Siang Guan Teoh Eng Khoon Lim Shea Lin Ng Hoong Kun Fun 《Journal of chemical crystallography》2008,38(5):345-350
Abstract The title compound, bis(2,4-dinitrobenzoato)tetrabutyldistannoxane(IV), was obtained from the reaction of di-n-butyltin(IV) oxide with 2,4-dinitrobenzoic acid. It crystallizes out as the usual dicarboxylatotetrabutyldistannoxane(IV)
dimer. In the monoclinic system P21/c, a = 12.391(3) ?, b = 19.937(5) ?, c = 15.026(4) ?, α = γ = 90°, β = 102.857(2)°, V = 3618.95(16) ?3 and Z = 2. A crystal structure determination of the title compound reveals the presence of a centrosymmetric planar Sn2O2, with two different environments for tin atoms and two distinct carboxylate groups. Two of the carboxylate groups are bonded
to the exocyclic tin atom in a bidentate bridging manner and the remaining two carboxylate groups are bonded to the tin atom
in a monodentate manner. As a result, both the tin atoms moieties in the complex are five coordinate and exhibit trigonal
bipyramid geometry.
Index Abstract Synthesis, Characterization and Crystal Structure of the Bis(2,4-dinitrobenzoato)tetrabutyldistannoxane(IV) Dimer
Yip Foo Win, Teoh Siang Guan, Lim Eng Khoon, Shea Lin Ng, Hoong Kun Fun
A crystal structure determination of the title compound reveals the presence of a centrosymmetric planar Sn2O2, with two different environments for tin atoms and two distinct carboxylate groups.
相似文献
75.
Computer vision has been gaining popularity for industrial applications, and the transputer offers a cost-effective vision hardware platform for an automated vision system. In this paper, component level inspection was carried out on the integrated circuit (IC), diode, resistor and capacitor. Board level inspection was also implemented for inspection of multiple ICs and missing components on assembled PCBs. The algorithms used were implemented for parallel processing using transputers. Through experiments, it was found that inspection of a component takes less than l.5 s, with an accuracy of above 85%. The transputer has also proven to out-perform sequential processing. The implementation of transputers for real-time image processing was successfully achieved. 相似文献
76.
Electrical resistivity (ρ) of amorphous Fe80B20 and Fe78Mo2B20 have been studied as a function of temperature (T) between 78 and 1000 K. The ρ vs T curves, obtained with specified warming and cooling rates, show that such curves are sensitive probes of the crystallization process. Within the experimental error, no anomalies in the ρ behavior can be seen at the Curie temperature of each amorphous alloy. 相似文献
77.
A well-defined, water-soluble, pH and temperature stimuli-responsive [60]fullerene (C(60)) containing ampholytic block copolymer of poly((methacrylic acid)-block-(2-(dimethylamino)ethyl methacrylate))-block-C(60) (P(MAA-b-DMAEMA)-b-C(60)) was synthesized by the atom transfer radical polymerization (ATRP) technique. The self-assembly behavior of the C(60) containing polyampholyte in aqueous solution was characterized by potentiometric and conductometric titration, dynamic light scattering (DLS), and transmission electron microscopy. This amphiphilic mono-C(60) end-capped block copolymer shows enhanced solubility in aqueous medium at room and elevated temperatures and at low and high pH but phase separates at intermediate pH between 5.4 and 8.8. The self-assembly of the copolymer is different from that of P(MAA-b-DMAEMA). Examination of the association behavior using DLS revealed the coexistence of unimers and aggregates at low pH at all temperatures studied, with the association being driven by the balance of hydrophobic and electrostatic interactions. Unimers and aggregates of different microstructures are also observed at high pH and at temperatures below the lower critical solution temperature (LCST) of PDMAEMA. At high pH and at temperatures above the LCST of PDMAEMA, the formation of micelles and aggregates coexisting in solution is driven by the combination of hydrophobic, electrostatic, and charge-transfer interactions. 相似文献
78.
Mohammad Akbar Ali Teoh S. Guan Palash Bhattacharjee Ray J. Butcher Yu Li 《Transition Metal Chemistry》1996,21(4):351-357
Summary New nickel(II) and copper(II) complexes of general formulae [M(Ap-SR)] and [Ap-SR)B] (Ap-SR = dianionic forms of the Schiff bases of 2-hydroxyacetophenone and S-alkyl esters of dithiocarbazic acid; M = NiII or CuII; R = Me or CH2Ph; B = py, phen or dipy have been synthesized and characterized by a variety of physicochemical techniques. Magnetic and spectroscopic data support an oxygen-bridged binuclear structure for the [M(Ap-SR)] complexes. The [M(Ap-SR)py] complexes are four-coordinate and square planar, whereas the [M(Ap-SR)B] complexes (B = phen or dipy) are five-coordinate and probably trigonal bipyramidal. The [Cu(Ap-SR)B] complexes (B = py, phen or dipy) obey the Curie-Weiss law over the 298-93 K range.The structure of the [Ni(Ap-SMe)py] complex has been determined by X-ray crystallography. It has an approximately square-planar structure in which the doubly-deprotonated Schiff base is coordinated to the NiII ion via the azomethine N atom, the phenolic O atom and the thiolato S atom. The fourth coordination position around the NiII ion is occupied by the N of the pyridine ligand. 相似文献
79.
Hermawan M Bushell GC Craig VS Teoh WY Amal R 《Langmuir : the ACS journal of surfaces and colloids》2004,20(15):6450-6457
This paper tests an approach to the estimation of relative particle bond strength based on the nondimensional floc and aggregation factors. The strength of flocs formed by aggregating nanosized silica particles with the addition of potassium chloride (KCl) or cationic surfactants, alkyltrimethylammonium bromide (mixture of CTAB, DTAB, and MTAB) was analyzed. The bonding force of the flocs formed in surfactant compared to that formed in the KCl system was estimated using the new dimensional analysis approach. This force ratio was then compared to that obtained by atomic force microscopy. 相似文献
80.