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91.
Binary and ternary blends composed of poly (lactic acid) (PLA), thermoplastic starch (TPS) and glycidyl methacrylate grafted poly (ethylene octane) (GPOE) were prepared using Haake Mixer. The mechanical morphology, thermal properties, water absorption, and degradation properties of the blends were also investigated. The elongation at break and impact strength of the ternary blends were greatly increased by the filling of GPOE. Compared to non-GPOE binary blends, the morphology of ternary blends with GPOE indicated that starch granules melted and there was good compatibility between PLA matrix and TPS. The mechanism and schematic diagram of the reactions in PLA, TPS, and GPOE were proposed and proved by testing and observing the morphology. Moreover, the biodegradation and thermal decomposition were studied through compost testing and thermal gravimetric analysis, respectively. Biodegradation results indicated that the blends have the excellent biodegrade ability.  相似文献   
92.
Thermogravity analysis (TGA) and differential scanning calorimetric (DSC) analysis, as well as dynamic thermal analysis (DMA), were carried out to study the interfacial interaction between wood flour (WF) and starch/cellulose acetate (SCA) blend. It was found that the main components in the compounds, namely, starch, cellulose, and cellulose acetate, started to decompose at around 330°C, a characteristic temperature for breaking glycoside-linked glucose units. Complexation of lignin in WF with amylose in SCA occurred during compounding, which gave rise to new crystallites that have a melting point of around 160°C. Hydrogen bonding is believed to play a key role in the crystallization. With increasing WF content, both the glass transition temperature and softening temperature increase as a result of the restricted molecular chain mobility imposed by rigid cellulose filaments. In addition, the DMA data revealed that amylose can occur as linkages in the crystallites. All these observations indicated that the interfacial adhesion between SCA and WF is relatively strong, even in absence of a coupling agent.  相似文献   
93.
研究了葡萄糖、果糖、蔗糖、马铃薯淀粉标准液、马铃薯粉渣和马铃薯淀粉深加工工艺废液,确定了蒽酮比色法测定马铃薯淀粉深加工废液总糖含量的最佳实验条件。在马铃薯淀粉深加工废液中加入盐酸,在105℃消煮120min,用活性碳脱色,过滤,滤液加入蒽酮,沸水浴中加热12min,显色体系在620nm处的吸光度达到最佳值,糖的浓度在1—100μg/mL范围内符合比耳定律,线性相关系数为0.9997。用所拟方法对凉山洲盐源世富农业科技公司马铃薯淀粉深加工工艺废液总糖进行测定,相对误差在5%以内,加标回收率在96.42%—103.16%之间,结果满意。  相似文献   
94.
This work aims to understand the effect of nanoparticle-enzyme interactions and how such interactions affect starch based soil removal. Silica and laponite are used as the model nanoparticles, and s-amylase is employed as the model enzyme. The results show that, if the nanoparticles and enzyme are added simultaneously, laponite enhances the enzyme performance toward starch soil removal, whereas silica imposes a small effect on the enzymatic activity towards the same soil substrates. However, when nanoparticles are added first, the enzyme activity is not affected much by laponite but is hindered significantly by silica nanoparticles. Furthermore, sequential addition of the enzyme followed by silica nanoparticles improves soil removal. Electron microscopic analyses, measurements of the enzyme activity in suspen- sions of nanoparticles, and particle size characterisation suggest that dense coverage of soil surface by the silica nanoparticles be likely a mechanism for the experimentally observed hindrance of soil removal when silica nanoparticles are added before enzyme.  相似文献   
95.
无机物对淀粉塑料力学性能影响的研究进展   总被引:1,自引:0,他引:1  
淀粉以其来源广、成本低、可完全降解的特点已成为制备生物可降解塑料的重要来源。近年来,淀粉塑料的研究和应用发展迅速,其核心是不断提高其各项使用性能(如力学、耐水性能等)。当前,无机或矿物填料被广泛应用于复合材料中来提高材料的性能,本文主要根据无机物的种类不同,综述了典型的氧化物、氢氧化物,以及碳酸盐、硅酸盐、磷酸盐等盐类对淀粉塑料力学性能的影响,归纳了近期的研究成果,分析了该领域研究的热点和难点,并对今后的发展趋势提出了展望。  相似文献   
96.
淀粉囊化农药控释缓释技术   总被引:10,自引:0,他引:10  
介绍了近20年来淀粉囊化农药控释缓释技术的研究和发展概况,详细综述和讨论了淀粉囊化技术的囊化方法、影响释放特性的主要因素、制品耐水性问题的解决办法、开发应用研究及发展前景。  相似文献   
97.
The incorporation of antimicrobials in foods by means of the use of films where they are entrapped collaborates to decrease their diffusion rate. In this work, the physicochemical properties of starch-based films loaded with 1% wt. natamycin were analyzed, and the antifungal activity of these films was evaluated against Penicillium spp..

Variations in the properties of films with 1% natamycin were minimal, leading to the conclusion that this material could be applied to avoid mold development on the surface semi-hard cheeses. Corn starch-based films containing natamycin at 1% w/w inhibited the Penicillium spp. growth in a solid matrix.  相似文献   

98.
Mn^3+引发淀粉与丙烯腈接枝共聚物的研究   总被引:1,自引:0,他引:1  
用过渡金属离子或其配合物引发淀粉的接枝共聚是一个饶有兴趣的课题。Ce~(4 )离子引发淀粉与烯类单体的接枝共聚已有广泛报道。Mehrotra等用稳定的[Mn(H_2P_2O_7)_3]~(3-)引发淀粉与烯类单体的接枝共聚取得了满意的结果。本文报道用电镜,x-射线衍射和热重分析等方法对这一接枝共聚物的形态、结构和热稳定性的研究结果。  相似文献   
99.
聚乙烯醇-淀粉共混溶液流变特性研究   总被引:5,自引:0,他引:5  
聚乙烯醇-淀粉共混溶液流变特性研究邱威扬,邱贤华,喻继文,吴素果(江西科学院应用化学研究所南昌330029)关键词聚乙烯醇,淀粉,共混,流变特性淀粉塑料是目前国内外研究的热点,各国已宣布研制成功多种淀粉塑料.据报道80年代末以来,生产量以75%的年增...  相似文献   
100.
High-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC–PAD) is a widely used technique to study the chain length distribution of amylopectin. The chromatograms, however, do not directly reflect this distribution, since the PAD response changes with the degree of polymerization. In this study, waxy maize starch was debranched and fractionated on a Bio-Gel P-6 column and the response factors for maltosaccharides with DP 3–65 were determined. The detector response per μg glucan chains was shown to decrease considerably for DP 3–7 while the curve leveled out for DP larger than 15.  相似文献   
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