Isolation of a thermostable trypsin inhibitor with exploitable potential

A novel trypsin inhibitor with considerable thermal and pH stability, designated Glytine, was isolated from seeds of the Chinese black soybean Glycine max (L.) Merr. The purification procedure involved ammonium sulfate precipitation, ion-exchange chromatography on CM-Sephadex C-50, gel filtration chromatography on Sephacryl S-200HR, and gel filtration chromatography on POROS HS-20. The 20 N-terminal amino acid sequences were determined to be DEYSKPCCDLCMCTRRCPPQ, demonstrating close homology with the sequences of leguminous trypsin inhibitors. The molecular mass and isoelectric point of the inhibitor were estimated by SDS-PAGE and isoelectric focusing to be 19.9 kDa and 6.2, respectively. Trypsin could be completely inhibited by Glytine when the weight ratio was 1.5. The inhibitory activity of Glytine was unaffected by exposure to temperatures up to 100 °C, or within the pH range 2–12. Besides trypsin–chymotrypsin inhibition activity, Glytine demonstrated other biological activities including antiproliferative activity against tumor cells including human liver hepatoma cells Bel-7402 and neuroblastoma cells SHSY5Y. In addition, the inhibitor showed antifungal activity against Pythium aphanidermatum, Fusarium oxysporum, Alternaria alternata (Fr.) Keiss, Fusarium solani, and Botrytis cinerea. This study extended research on leguminous trypsin–chymotrypsin inhibitor and suggested exploitable potential.     

Femtocell技术的由来、优势和市场前景

Femtocell是用于增强室内无线覆盖的一项新技术,近年来受到了业界的广泛注意,发展十分迅速。本文叙述了Femtocell技术的由来和发展;讨论了Femtocell系统的优越性和需解决的关键技术;介绍了国外业界对Femtocell市场的预测。     

流态化还原铁矿粉技术前景分析

从资源条件趋势的角度分析了中国需要流态化还原铁矿粉技术的必要性。中国巨大的钢铁需求和废钢严重不足,为流态化技术的推广提供了广阔空间,同时中国社会经济的发展和煤炭资源的相对优势,也为流态化技术的完善和真正实现工业化提供了条件和机会。     

浅谈软开关技术

着重介绍软开关技术的工作原理，设计方案及分析方法。     

建筑施工企业的资源规划(ERP)应用软件

建筑施工企业为在建筑市场占据更多份额 ,必需从质量、成本、工期等各方面提高自身竞争能力 ,而企业资源规划理念和网络科技、电子商务的结合 ,提供了一条在施工过程过程中动态地对企业和力、设备、资金、技术、信息等各个方面 (统称为资源 )作出合理配置、储存、调拨及运用 ,从而最大限度地降低成本、提高效率的有效途径。简要介绍了其相应软件开发的主要目标和基本内容。     

数据挖掘技术在CRM中的应用

利用数据挖掘可以帮助完成日益繁重的潜在客户群的划分,从而实现对获取新客户成本的有效管理,可以明显提高营销活动的响应率,改善营销活动的回报率。在分析数据挖掘应用于客户关系管理的必要性和应用方式的基础上,对面向数据挖掘的通信企业客户关系管理系统和数据挖掘在其中的具体应用进行了研究。     

内置横向插板加强型管节点静力强度研究

主管内设置横向插板是改善焊接圆钢管结构承载能力的一种方法。为了研究横向内置插板对节点静力强度的影响，采用有限元方法，对62个加强与未加强的T形节点模型进行了有限元模拟和分析。调查了节点区域和内置横向插板在静力加载过程中的变形过程。通过对模型参数的研究发现：内置横向插板能够提高T形节点的静力强度，但当T形节点承受轴向压力作用时，静力强度的提高对插板长度和厚度的变化不敏感。插板的厚度可按照构造措施选取，长度不能小于支管的直径。     

Key-Attributes-Based Ensemble Classifier for Customer Churn Prediction

Recently, it has been seen that the ensemble classifier is an effective way to enhance the prediction performance. However, it usually suffers from the problem of how to construct an appropriate classifier based on a set of complex data, for example, the data with many dimensions or hierarchical attributes. This study proposes a method to constructe an ensemble classifier based on the key attributes. In addition to its high-performance on precision shared by common ensemble classifiers, the calculation results are highly intelligible and thus easy for understanding. Furthermore, the experimental results based on the real data collected from China Mobile show that the key-attributes-based ensemble classifier has the good performance on both of the classifier construction and the customer churn prediction.     

Hydrothermal-assisted synthesis of surface aluminum-doped LiCoO2 nanobricks for high-rate lithium-ion batteries

LiCoO₂ nano-particles precursor was synthesized through a mixed-alkalis (LiOH-NaOH) hydrothermal reaction, and finally sintered into LiCoO₂ nanobricks with a sickness of ~300?nm. This LiCoO₂ nanobrick cathode delivered a specific capacity of 131.8 mAh g^?1 at 1?C between 3.0 and 4.2?V and 90% capacity retention after 100 cycles. Those synthesized LiCoO₂ nanobricks were further treated by surface Al³⁺ doping to achieve much enhanced 4.5?V lithium storage capability and cycling stability. EIS results showed the surface Al³⁺ doping operation can signification decrease the charge-transfer resistances of the LiCoO₂ cathodes for both before and after cyclings.     

Study on oxygen activation and methane oxidation over La0.8Sr0.2MnO3 electrode in single-chamber solid oxide fuel cells via an electrochemical approach

Single-chamber solid oxide fuel cells (SC-SOFCs), which apply fuel-oxidant (air) gas mixture as the atmosphere for both anode and cathode, are receiving many interests recently. This study aims to clarify the mechanism of oxygen reduction and methane oxidization over La_0.8Sr_0.2MnO₃ (LSM) cathode in SC-SOFCs by an electrochemical method in combination with mass spectrometry (MS). Before cathodic polarization, a large polarization resistance (R_p) for oxygen reduction reaction (ORR) was observed and methane did not cause obvious effect on ORR because of the weak adsorption of methane over LSM surface. Cathodic polarization could decrease the R_p obviously due to the in-situ creation of oxygen vacancies; methane likely adsorbed on those oxygen vacancy sites to enhance its effect on ORR. Both the anodic and cathodic polarizations significantly increased the rate of methane oxidation over LSM electrode; in particular, the pumped oxygen anion was highly active for methane oxidation.