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101.
选取一定混合比例的玉米秸秆与塑料PE制成混合燃料,采用固定床实验台,通过改变反应温度,并结合化学热力学平衡分析、X射线衍射及扫描电子显微电镜能谱分析技术对共气化过程中碱金属的迁移行为进行研究。结果表明,气化气中碱金属以气态组元KCl、K2Cl2、NaCl形式存在。混合燃料中掺入塑料PE后,C、H含量增加,H使得共气化反应中更容易与Cl反应生成HCl,而非KCl,同时C更容易与K结合,导致K的释放率低于单独玉米秸秆气化,但使Na释放率增加。灰中碱金属化合物以KCl、NaCl、K2SO4、KAlSi3O8、KAlSiO4、NaAlSi3O8、NaAlSiO4为主,气化温度高于800℃后灰中K、Na、Cl更易沉积于微孔边缘。 相似文献
102.
Hyang-Ok Kim Young-Jung Wee Jin-Nam Kim Jong-Sun Yun Hwa-Won Ryu 《Applied biochemistry and biotechnology》1996,131(1-3):694-704
The fermentative production of lactic acid from cheese whey and corn steep liquor (CSL) as cheap raw materials was investigated
by using Lactobacillus sp. RKY2 in order to develop a cost-effective fermentation medium. Lactic acid yields based on consumed lactose were obtained
at more than 0.98 g/g from the medium containing whey lactose. Lactic acid productivities and yields obtained from whey lactose
medium were slightly higher than those obtained from pure lactose medium. The lactic acid productivity gradually decreased
with increase in substrate concentration owing to substrate and product inhibitions. The fermentation efficiencies were improved
by the addition of more CSL to the medium. Moreover, through the cell-recycle repeated batch fermentation, lactic acid productivity
was maximized to 6.34 g/L/h, which was 6.2 times higher than that of the batch fermentation. 相似文献
103.
A new analytical methodology based on capillary electrophoresis-mass spectrometry (CE-MS(2)) is presented in this work, enabling the identification and determination of six non-protein amino acids (ornithine, β-alanine, GABA, alloisoleucine, citrulline and pyroglutamic acid) in vegetable oils. This methodology is based on a previous derivatization with butanol and subsequent separation using acidic conditions followed by on-line coupling to an ion trap analyzer for MS(2) detection established through an electrospray-coaxial sheath flow interface. The electrophoretic and interface parameters were optimized obtaining the separation of all compounds in less than 15 min and with resolutions higher than 5. The proposed method was validated by assessing its accuracy, precision (RSD<7% for corrected peak areas), LODs and LOQs (between 0.04-0.19 ng/g and 0.06-0.31 ng/g, respectively) and linearity range (R(2)>0.99), and it was used in order to identify the selected non-protein amino acids in soybean oils, sunflower oils, corn oils and extra virgin olive oils. MS(2) experiments performed the fingerprint fragmentation of these compounds allowing to corroborate ornithine and alloisoleucine in seed oils but not in olive oils. The method was applied to identify and quantify olive oil adulterations with soybean oil detecting in a single run the amino acids in mixtures up to 2% (w/w). The results showed a high potential in using these compounds as novel markers for the detection of adulterations of extra virgin olive oils with seed oils. Thus, the developed method could be considered a simple, rapid and reliable method for the quality evaluation of extra virgin olive oil permitting its authentication. 相似文献
104.
提出了一种基于离散傅里叶变换(discrete Fourier transform,DFT)的玉米品种特征分析新方法.实验数据为37个玉米晶种种子的近红外漫反射光谱数据,波段范围为4 000~12 000 cm-1.文中通过对原始数据进行分析,发现扫描频率较高的部分噪声也比较大.文中首先定义了一种类间、类内差异度Qm的... 相似文献
105.
精确反演农作物冠层叶面积指数对指导作物管理和作物估产具有非常重要的意义。以吉林市郊区玉米种植区为试点,考虑冠层叶片水分含量对LAI的贡献,在NDVI的基础上结合表征冠层叶片水分含量的植被指数DSWI,提出一种归一化综合植被指数NCVI,以此建立模型反演LAI,并对模型进行检验。结果表明:NCVI模型反演LAI值与实测值之间存在良好的对应关系,此模型突破了传统经验模型对稠密冠层LAI反演的局限,对LAI值大于3的冠层反演效果良好;另外,NCVI模型对土壤水环境十分敏感,在干旱半干旱地区的反演效果明显优于一般区域。 相似文献
106.
107.
玉米种子穗腐病是危害玉米产量的主要病害之一。利用近红外光谱开展了玉米种子穗腐病判别模型研究。246粒玉米种子由吉林省农业科学院海南育种基地提供,其中96粒玉米种子为穗腐病染病样本,其他150粒玉米种子为同种玉米正常样本。利用MATRIX-Ⅰ型傅里叶近红外光谱仪采集了样本800~2 500 nm范围的近红外光谱信息,并对样本近红外光谱数据利用多元散射校正(MSC)进行预处理。结合玉米内部有机物质的近红外光谱的敏感波段和样本近红外光谱吸收峰挑选了4个优选区间,并采用相关系数法(CA)、连续投影算法(SPA)和竞争性自适应重加权算法(CARS)三种不同原理的特征波长提取算法分别提取了4(1 362,1 760,2 143和2 311 nm)、5(1 227,1 310,1 382,1 450和1 728 nm)和10(1 232,1 233,1 257,1 279,1 313,1 688,1 703,1 705,2 302和2 323 nm)个特征波长。以提取得到的特征波长作为玉米种子穗腐病判别模型输入变量,用0-1(染病-正常)表示样本染病状况作为输出真实值建立支持向量机(SVM)模型,使用网格搜索法结合十折交叉验证法对模型参数进行优化。结果表明,CA-SVM,SPA-SVM和CARS-SVM三种判别模型中训练集和测试集建模准确率均在90%以上。该研究成果为玉米种子病害诊断装置提供了模型基础,且针对优选区间进行特征波长选择的方式也可以为建立其他种子病害判别模型提供参考。 相似文献
108.
In order to improve iron chelating ability and retain the activity of functional peptide, corn peptide was chelated with iron to form corn ACE inhibitory peptide-ferrous chelate (CP-Fe) treated by dual-frequency ultrasound. Furthermore, the chelating mechanism was revealed by analyzing various structural changes, and the stability was further evaluated. Under this study condition, the iron-binding capacity of corn ACE inhibitory peptide (CP) and chelate yield reached 66.39% and 82.87%, respectively. Ultrasound-treated CP exhibited a high iron chelating ability, meanwhile, chelation reaction had no significant effect on the ACE inhibition activity (82.21%) of the peptide. CP-Fe was formed by binding the peptides amino, carbonyl and carboxyl groups with Fe2+ demonstrated by Ultra-violet spectroscopy, Fourier transform infrared characterization, X-ray diffraction, energy dispersion spectrum, zeta potential, amino acid composition and other multi-angle analyses. Moreover, ultrasound-treated CP-Fe chelate exhibited porous surface and uniform nanoparticle shape. Furthermore, ultrasound-treated CP-Fe chelate exhibited an excellent stability towards various pH (retention rate ≥ 95.47% at pH 6–10), temperatures (retention rate ≥ 85.10% at 25–70 °C), and gastrointestinal digestion (retention rate 79.18%). Overall, ultrasound-treated CP-Fe chelate possessed high iron-chelating ability, ACE inhibition activity and stability. This study provides a novel synthesis method of the iron-chelating corn ACE inhibitory peptide, which is promising to be applied as iron supplements with high efficiency, bioactivity, and stability. 相似文献
109.
J. Richard Hess Kevin L. Kenney Christopher T. Wright Robert Perlack Anthony Turhollow 《Cellulose (London, England)》2009,16(4):599-619
As biorefining conversion technologies become commercial, feedstock availability, supply system logistics, and biomass material
attributes are emerging as major barriers to the availability of corn stover for biorefining. While systems do exist to supply
corn stover as feedstock to biorefining facilities, stover material attributes affecting physical deconstruction, such as
densification and post-harvest material stability, challenge the cost-effectiveness of present-day feedstock logistics systems.
In addition, the material characteristics of corn stover create barriers with any supply system design in terms of equipment
capacity/efficiency, dry matter loss, and capital use efficiency. However, analysis of a conventional large square bale corn
stover feedstock supply system concludes that (1) where other agronomic factors are not limiting, corn stover can be accessed
and supplied to a biorefinery using existing bale-based technologies, (2) technologies and new supply system designs are necessary
to overcome biomass bulk density and moisture material property challenges, and (3) major opportunities to improve conventional
bale biomass feedstock supply systems include improvements in equipment efficiency and capacity and reducing biomass losses
in harvesting, collection, and storage. Finally, the backbone of an effective stover supply system design is the optimization
of intended and minimization of unintended material property changes as the corn stover passes through the individual supply
system processes from the field to the biorefinery conversion processes.
相似文献
J. Richard HessEmail: |
110.
Summary of findings from the Biomass Refining Consortium for Applied Fundamentals and Innovation (CAFI): corn stover pretreatment 总被引:1,自引:0,他引:1
Richard T. Elander Bruce E. Dale Mark Holtzapple Michael R. Ladisch Y. Y. Lee Colin Mitchinson John N. Saddler Charles E. Wyman 《Cellulose (London, England)》2009,16(4):649-659
The Biomass Refining Consortium for Applied Fundamentals and Innovation, with members from Auburn University, Dartmouth College,
Michigan State University, the National Renewable Energy Laboratory, Purdue University, Texas A&M University, the University
of British Columbia, and the University of California at Riverside, has developed comparative data on the conversion of corn
stover to sugars by several leading pretreatment technologies. These technologies include ammonia fiber expansion pretreatment,
ammonia recycle percolation pretreatment, dilute sulfuric acid pretreatment, flowthrough pretreatment (hot water or dilute
acid), lime pretreatment, controlled pH hot water pretreatment, and sulfur dioxide steam explosion pretreatment. Over the
course of two separate USDA- and DOE-funded projects, these pretreatment technologies were applied to two different corn stover
batches, followed by enzymatic hydrolysis of the remaining solids from each pretreatment technology using identical enzyme
preparations, enzyme loadings, and enzymatic hydrolysis assays. Identical analytical methods and a consistent material balance
methodology were employed to develop comparative sugar yield data for each pretreatment and subsequent enzymatic hydrolysis.
Although there were differences in the profiles of sugar release, with the more acidic pretreatments releasing more xylose
directly in the pretreatment step than the alkaline pretreatments, the overall glucose and xylose yields (monomers + oligomers)
from combined pretreatment and enzymatic hydrolysis process steps were very similar for all of these leading pretreatment
technologies. Some of the water-only and alkaline pretreatment technologies resulted in significant amounts of residual xylose
oligomers still remaining after enzymatic hydrolysis that may require specialized enzyme preparations to fully convert xylose
oligomers to monomers. 相似文献