Enhancement of green emission by the codoping U . 3＋ A＋ （A - Li, Na, K） in Ca2 O3CI.Tb phosphor

Tb3＋-doped Ca2BO3C1 compounds with different charge compensation approaches are synthesized by a hightemperature solid-state reaction method, and the luminescent properties and Commission Internationale de l＇Eclairage （CIE） chromaticity coordinates are systematically characterized. Ca2BO3Cl：Tb3＋ can produce green emission under 376 nm radiation excitation. With codoped A＋ （A = Li, Na, K） as charge compensators, the relative emission intensities of Ca2BO3Cl：Tb3＋ are enhanced by about 1.61, 1.97, and 1.81 times compared with those of the direct charge balance, which is considered to be due to the effect of the difference in ion radius on the crystal field. The CIE chromaticity coordinates of Ca2BO3CI：Tb3＋, A＋ （A = Li, Na, K） are （0.335, 0.584）, （0.335, 0.585）, and （0.335, 0.585）, corresponding to the hues of green. Therefore, A＋ （A = Li, Na, K） may be the optimal charge compensator for Ca2BO3Cl：Tb3＋.     

Ab initio MRCI＋Q study on potential energy curves and spectroscopic parameters of low-lying electronic states of CS＋

Carbon monosulfide molecular ion （CS＋）, which plays an important role in various research fields, has long been attracting much interest. Because of the unstable and transient nature of CS＋, its electronic states have not been well investigated. In this paper, the electronic states of CS＋ are studied by employing the internally contracted multireference configuration interaction method, and taking into account relativistic effects （scalar plus spin–orbit coupling）. The spin–orbit coupling effects are considered via the state-interacting method with the full Breit–Pauli Hamiltonian. The potential energy curves of 18 Λ–S states correlated with the two lowest dissociation limits of CS＋ molecular ion are calculated, and those of 10 lowest Ω states generated from the 6 lowest Λ–S states are also worked out. The spectroscopic constants of the bound states are evaluated, and they are in good agreement with available experimental results and theoretical values. With the aid of analysis of Λ–S composition of Ω states at different bond lengths, the avoided crossing phenomena in the electronic states of CS＋ are illuminated. Finally, the single ionization spectra of CS （X1Σ＋） populating the CS＋（X2Σ1/2＋, A2Π3/2, A2Π1/2, and B2Σ1/2＋） states are simulated. The vertical ionization potentials for X2Σ1/2＋, A2Π3/2, A2Π1/2, and B2Σ1/2＋ states are calculated to be 11.257, 12.787, 12.827, and 15.860 eV, respectively, which are accurate compared with previous experimental results, within an error margin of 0.08 eV~0.2 eV.     

Relativistic R-matrix studies of photoionization processes of Ar^5＋

The 3s–np photoionization processes of the ground state 2P1/2 and the metastable state 2P3/2 of Ar5＋ are investigated using our recently developed relativistic R-matrix code, where the interactions between the bound states and the continuum states are included. Both resonance positions and the oscillator strengths are in much better agreement with the absolute experimental measurements by Wang et al.[Wang J C, Lu M, Esteves D, Habibi M, Alna’washi G and Phaneuf R A 2007 Phys. Rev. A 75 062712] with a resolution of 80 meV than their theoretical results. The contributions of the two experimental unresolved transitions are distinguished in our calculations, which show that the transitions from the ground state also make significant contributions to some resonances. Our theoretical results are also in good agreement with the measurements for the first resonance with a higher resolution of 20 meV.     

Novel Wronskian Condition and New Exact Solutions to a （3＋1）-Dimensional Generalized KP Equation

Utilizing the Wronskian technique, a combined Wronskian condition is established for a （3＋1）-dimensional generalized KP equation. The generating functions for matrix entries satisfy a linear system of new partial differential equations. Moreover, as applications, examples of Wronskian determinant solutions, including N-soliton solutions, periodic solutions and rational solutions, are computed.     

Integrable Coupling of （2＋1）-Dimensional Multi-component DLW Integrable Hierarchy and Its Hamiltonian Structure

A new multi-component Lie algebra is constructed, and a type of new loop algebra is presented. A （2＋1）-dimensional multi-component DLW integrable hierarchy is obtained by using a （2＋1）-dimensional zero curvature equation. Furthermore, the loop algebra is expanded into a larger one and a type of integrable coupling system and its corresponding Hamiltonian structure are worked out.     

On an entropy of ℤ + k -actions

In this paper,a definition of entropy for Z＋k（k≥2）-actions due to Friedland is studied.Unlike the traditional definition,it may take a nonzero value for actions whose generators have finite（even zero） entropy as single transformations.Some basic properties are investigated and its value for the Z＋k-actions on circles generated by expanding endomorphisms is given.Moreover,an upper bound of this entropy for the Z＋k-actions on tori generated by expanding endomorphisms is obtained via the preimage entropies,which are entropy-like invariants depending on the ＂inverse orbits＂ structure of the system.     

应用科技大学模式下的工业工程专业英语教学初探

在应用科技大学教学模式下,为实现工业工程专业英语教学目标,针对专业英语特点,思考专业英语的教学现状及存在问题,设计以学生为中心的教学模式,搭建专业英语教学资源共享平台,丰富、整合和延伸教学内容,基于任务驱动学习,从教材选择、教学方法、考核方式方面进行改革,提高专业英语教学质量。     

费尔干猪毛菜液泡膜氢离子焦磷酸酶基因SfVP的克隆、序列分析及表达

植物液泡膜氢离子焦磷酸酶(Vacuolar H+-PPase,VP)能够酸化液泡并为液泡的次级转运系统提供能量,在植物耐盐性方面发挥着着重要作用。本研究采用RT-PCR结合RACE方法,从费尔干猪毛菜中(Salsola ferganica)克隆得到液泡膜质子焦磷酸酶基因SfVP,该基因的cDNA全长2738 bp,包含1个2301 bp的完整开放读码框(ORF),编码766个氨基酸的多肽。氨基酸序列分析表明其属于H+-转运无机焦磷酸酶超家族成员,具有典型的H+-PPase结构域,其疏水性较强,含有12个跨膜螺旋结构。SfVP序列比对显示具有H+-PPase的3个保守序列CS1、CS2和CS3,其中CS1中含有保守的底物催化位点,与烟草的NtVP氨基酸序列相似性为95.3%。半定量RT-PCR结果表明,SfVP的转录表达丰度随着600 mmol/L NaCl处理时间的增加而升高,处理12 h后显著增加并一直维持在较高水平。     

聚苯乙烯-硫脲/二氧化钛复合材料对水中铅和汞离子吸附的研究

用γ-甲基丙烯酰氧基丙基三甲氧基硅烷作为偶联剂,对纳米二氧化钛进行表面改性,以偶氮二异丁睛为引发剂,使苯乙烯和烯丙基硫脲在其表面发生聚合,制成了聚苯乙烯-烯丙基硫脲/二氧化钛复合材料。用红外光谱、扫描电子显微镜/X射线能谱对合成材料进行结构及元素组成分析。将聚苯乙烯-硫脲/二氧化钛复合材料作为固相萃取填料,制成固相萃取小柱,富集水中Pb2+和Hg2+,以硝酸和三乙醇胺的混合液作为洗脱剂洗脱目标化合物。采用ICP/MS分析法测定Pb2+和Hg2+的含量。实验结果表明:合成的聚苯乙烯-硫脲/二氧化钛复合材料作为固相萃取填料对Pb2+和Hg2+的吸附容量分别为16.5 mg/g和18.9 mg/g,SPE-ICP/MS测定水中Pb2+和Hg2+的最低检出限分别为0.012μg/L和0.048μg/L。     

Development of emergency water quality standard for Cr6+ and Hg2+ in Liao River basin

The acute toxicity data of Cr＋ and Hg2＋ to the aquatic organisms in Liao River basin was collected and screened. Calculated results of criteria values using popular species sensitivity distribution （SSD） methods were evaluated through data analysis. The comprehensive methodology of emergency water quality standards （EWQSs） was established on the basis of the SSD method of Australia and New Zealand according to the evalu- ation results. The affected fractions of the aquatic organisms were set to be 5 %, 15 %, 30 % and 50 %, corre- sponding to the risk grades of Ⅰ,Ⅱ,Ⅲ and IV, and four-grade EWQSs, respectively. The EWQSs for Cr6＋ and Hg2. in the Liao River were derived and the corresponding risk indicators were also proposed. The results showed that the four-grade EWQSs for Cr6＋ were 2.85 μg/L, 21.0 μg/L, 161 μg/L and 797 μ/L, respec- tively, and the risk indicators were daphnia （grade Ⅱ ）, shrimp （grade Ⅲ）, and the bighead fish or tadpole （grade IV）. The four-grade EWQSs for Hg2＋ were 0.59 μg/L, 2.32 μg/L, 6.25 μg/L and 15.6 μg/L, respective- ly, and the risk indicators were crucian carp or daphnia （grade Ⅱ）, shrimp （grade Ⅲ）, and worm or crab （grade IV）. The results provided valuable information for the risk analysis of sudden ambient water environmen- tal pollution accident.