One convenient synthesis route to boron nitride nanotube

We describe one convenient synthesis route to boron nitride (BN) nanotube by the reaction of boron powder, iron oxide, and ammonium chloride at 600 °C for 12 h. Characterized by XRD, FTIR, XPS, TEM and SAED, the composition and morphology of the products are confirmed. The possible reaction mechanism is also discussed.     

The Fundamental Experiments of Red Tide Chemical Forecast

Many food algae and red tide algae were cultivated in the f/2 medium, and the nitric oxide (NO) concentration of the medium and the cell density were determined. The experiments on algae were conducted when different concentrations of NO were added into the medium using two methods. The results show that low concentrations of NO were self-produced by marine algae during the exponential growth period and were about nmol/L level. But at the end of the period, i.e., 2 or 3 days before the cell density reaches the maximum, an NO peak appeared, with the NO concentration reaching 10 nmol/L. The NO threshold concentration exists according to the influence of exogenous NO on the marine phytoplankton growth. One type is the threshold concentration that can promote algae growth, and its value is between 10 and 1 nmol level, or even lower. The other type can inhibit the phytoplankton growth, which is about μmol level or higher. The results indicate that red tide algae are far more sensitive to NO than are food algae. The fundamental experimental outcome above may provide a new clue for red tide chemical forecast by inspecting the NO change.     

人文视野里的语文和语文教育

人文是人对自身本质特性的思索和探寻,包括理想人性及其实现方式,这种实现方式在人类社会主要体现为文化行为.人文视野里的语文表现出学科文化内蕴的综合性,言语符号内容与形式的同步性,人文精神展示的完整性等突出特点.要在语文教学中凸现人文性,必须注重教学行为的人文方式,教学材料的人文底蕴,文本解读的人文基点.     

基于Windows NT的HRPS-Ⅱ设备的控制系统设计

介绍了华中科技大学开发的HRPS-Ⅱ型选择性激光烧结设备的体系结构，根据选择性激光烧结的工作原理并结合该系统的硬件结构开发了基于NT操作系统下的控制软件．该控制软件是一种分层的结构，各个不同优先级的任务在不同的层面上运行，实时性强的部分运行在硬件中断级别上，对控制软件的关键性技术进行了描述．通过试验运行，该设备成功地加工出了复杂的原型件，证明控制系统开发是成功的．     

制定企业标准，为企业发展保驾护航——论富阳市涂布白纸板生产企业制定企业标准的必要性

GB／T103354—2004《涂布纸和纸板涂布白纸板》对富阳市涂布白纸板生产实际存有不适用之处，为符合法律法规和企业自身发展需求，企业必须制定充分反映市场、用户和消费者要求的企业标准。     

Dialdehyde starch‐crosslinked chitosan films and their antimicrobial effects

For improved mechanical and water‐swelling properties of chitosan films, a series of transparent films were prepared with dialdehyde starch as a crosslinking agent. Fourier transform infrared and X‐ray analysis results demonstrated that the formation of Schiff's base disturbed the crystallization of chitosan. The mechanical properties and water‐swelling properties of the films were significantly improved. The best values of the tensile strength and breaking elongation were 113.1 MPa and 27.0%, respectively, when the dialdehyde starch content was 5%. All the crosslinked films still retained obvious antimicrobial effects toward S. aureus and E. coli, and they showed potential for biomedical applications. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 993–997, 2003     

Difference in micellar properties of sodium dodecyl sulfonate from sodium 4-decyl naphthalene sulfonate in D2O solution studied by 1H NMR relaxation and 2D NOESY

¹H chemical shift changes of sodium 4-decyl naphthalene sulfonate (SDNS) at 313 K show that its critical micellar concentration lies between 0.82 and 0.92 mmol/dm³, which is in the same range as that of the previous study at 298 K. The spin–lattice relaxation time, spin–spin relaxation time and two-dimensional nuclear Overhauser enhancement spectroscopy experiments give information about the structure of the SDNS micelle and the dynamics of the molecules in the micelle. The size of the SDNS micelle remains almost unchanged in the temperature range from 298 to 313 K as deduced by analyzing the self-diffusion coefficient. Special arrangement of the naphthyl rings of SDNS in the micelles affects the packing of these hydrophobic chains. The methylene groups of the alkyl chain nearest the naphthalene groups penetrate into the aromatic region, which results in a more tightly packed hydrophobic micellar core than that of sodium dodecyl sulfonate.     

"受迫振动共振"演示实验的改进

高一物理新教材第九章第七节受迫振动共振中出现了三种频率：物体受迫振动的频率、驱动力的频率和物体的固有频率，对三种频率的理解学生感到困难；其次，对共振曲线的理解也感到很抽象。为此，对本节演示实验进行了较科学的改进，收到了很好的效果。     

论中部崛起进程中的江西教育发展战略

新时期,江西提出并实施了要在中部地区快速崛起的发展战略。在这一过程中,江西教育发展面临着极好的机遇,同时,也遭遇到了八个方面的挑战。于是,江西省委省政府提出了江西教育发展的总体要求。江西广大教育行政部门和教育工作者只要不断沿着中央指出的方向,落实省委省政府的部署,埋头苦干、扎实工作,就一定能为建设创新创业江西、绿色生态江西、和谐平安江西,为江西在中部地区的早日崛起提供有力的人才支持、知识基础和文化贡献,就一定能铸造出江西教育事业新的辉煌。     

The numerical approximation of center manifolds in Hamiltonian systems

In this paper we develop a numerical method for computing higher order local approximations of center manifolds near steady states in Hamiltonian systems. The underlying system is assumed to be large in the sense that a large sparse Jacobian at the equilibrium occurs, for which only a linear solver and a low-dimensional invariant subspace is available. Our method combines this restriction from linear algebra with the requirement that the center manifold is parametrized by a symplectic mapping and that the reduced equation preserves the Hamiltonian form. Our approach can be considered as a special adaptation of a general method from Numer. Math. 80 (1998) 1-38 to the Hamiltonian case such that approximations of the reduced Hamiltonian are obtained simultaneously. As an application we treat a finite difference system for an elliptic problem on an infinite strip.