《昭明文选》与“选学”的兴起

结合《文选序》及相关文献,探讨《昭明文选》包含的文学观念及文体分类思想,进而梳理《文选》成学的文献依据,兼具文学史、学术史、文化史等多方面价值。

Development and Application of Detection Methods for Capture and Transcription Elongation Rate of Bacterial Nascent RNA

Objective Detection and quantification of RNA synthesis in cells is a widely used technique for monitoring cell viability,health,and metabolic rate.After exposure to environmental stimuli,both the internal reference gene and target gene would be degraded.As a result,it is imperative to consider the accurate capture of nascent RNA and the detection of transcriptional levels of RNA following environmental stimulation.This study aims to create a Click Chemistry method that utilizes its property to capture nascent RNA from total RNA that was stimulated by the environment.Methods The new RNA was labeled with 5-ethyluridine(5-EU)instead of uracil,and the azido-biotin medium ligand was connected to the magnetic sphere using a combination of“Click Chemistry”and magnetic bead screening.Then the new RNA was captured and the transcription rate of 16S rRNA was detected by fluorescence molecular beacon(M.B.)and quantitative reverse transcription PCR(qRT-PCR).Results The bacterial nascent RNA captured by“Click Chemistry”screening can be used as a reverse transcription template to form cDNA.Combined with the fluorescent molecular beacon M.B.1,the synthesis rate of rRNA at 37℃is 1.2 times higher than that at 15℃.The 16S rRNA gene and cspI gene can be detected by fluorescent quantitative PCR,it was found that the measured relative gene expression changes were significantly enhanced at 25℃and 16℃when analyzed with nascent RNA rather than total RNA,enabling accurate detection of RNA transcription rates.Conclusion Compared to other article reported experimental methods that utilize screening magnetic columns,the technical scheme employed in this study is more suitable for bacteria,and the operation steps are simple and easy to implement,making it an effective RNA capture method for researchers.

试论钱钟书先生在文选学领域的卓越贡献

钱钟书先生的巨著《管锥编》中包含着研究《文选》的丰硕成果。本文从三个方面进行了纳结:一是推扬萧统的编选能力和"文选学"的重要性;二是在理论实践两方面突出了《文选》评点的价值;三是运用循环阐释方法补正李善的注文。

英语世界《文选》译介与研究

自20世纪初阿瑟·韦利首次译介《文选》以来,英语世界《文选》的译介与研究已有百余年的历程。本文选取11个英语世界最具代表性的《文选》节译本,历时梳理《文选》在英语世界的译介历程,厘清不同阶段的译介特征及重大发现。研究发现,随着中西学术交流步伐的加快,英语世界《文选》的译介与研究取得了长足的进步,从一开始的译介逐步深入到《文选》的本体研究,内容涉及作品阐释、文体分类、编撰和选录标准等方面,与国内“新文选学”研究内容趋同,可相互参益,且在版本、注释、校勘等方面,仍有很大的研究空间。中西学者应通力合作,充分发挥各自语言与文化优势,构建健全的中西学术交流话语体系,助推英语世界《文选》全译本的诞生,进而切实有效地促进英语世界“选学”新发展。

萧统编《文选》之深意

《文选》一书的选录标准以及编排体制是"选学"界讨论的热点。对于这一问题,不仅要从《文选序》入手进行分析,还要将《文选序》和选文相结合,以此来探讨《文选》的选文标准、选文内涵、编排意图和编排次序,从而揭示萧统编《文选》的深刻意旨。

“文选烂,秀才半”:《文选》

通过介绍《昭明文选》是一部什么样的书,什么叫"《文选》学",今天应该怎样读《文选》,我们可以了解《文选》的前世今生,可以充分利用这部书。

Study on Screening of Fungi with High-resistance against Chromium and on Related Characteristics

[Objective] The aim was to separate chromium-resistant microorganism from soil contaminated by chromium.[Method] Separation and purification technique was used as follows：different concentrations of Cr^6＋ were added into medium,and chromium-resistant fungi were screened after separations and domestications.The selected fungi were under preliminary identification according to its morphological and colony characteristics.Then,related biological characteristics were studied,including measurement of growth curve,growing effects by temperature,pH value and osmotic pressure.[Result] The Cr（VI） with concentration of 1 000 mg/L was separated and selected from soils in ten different places contaminated seriously by heavy metal in adjacent region of Yulin City.Considering its morphological and colony characteristics,it was preliminarily identified as saccharomycetes,which can well grow within 15-37 ℃,and whose most suitable temperature was 28℃.Bacterial strain can grow well with pH of 4-10,and the optimum pH was 7.2;besides,it can grow well with NaCl concentration of 0.5%-5.0%.Through the experiment,the bacteria was found with resistance not only to chromium,but also to heavy metals such as Pb＋Cu,Cu＋Fe,Pb＋Fe,and Pb＋Cu＋Fe.[Conclusion] The fungi selected from the experiment were of good adaptability to natural environment,and it also had resistance to other heavy metals.

Studies on the Isolation and Screening of α-amylase Producing Strain and Their Enzymatic Properties

[Objective] The aim was to obtain α-amylase producing strains with some excellent properties like high temperature resistance,strong acid resistance,strong alkali resistance,etc..[Method] α-amylase producing strains were isolated and screened; furthermore their enzymatic properties were studied.[Result] 10 strains with an obvious starch hydrolysis cycle were screened out from starch screening plate coated by diluted sample,from which 3 strains with higher α-amylase activity were screened out,that was X6,X8 and X10.As for X6,X8 and X10,their optimum pH values all belonged to neutral,and their optimum temperatures were all 60 ℃.Meanwhile,Ca^2＋ could increase their enzyme thermal stability.When the concentration of Ca^2＋ was 0.02-0.04 mol/L,the enzyme thermal stability of X6 and X8 reached the highest; When the concentration of Ca^2＋ was 0.03-0.04 mol/L,that of X10 reached the highest; When the concentration of Ca^2＋ was increased continuously,those of the 3 strains all decreased.[Conclusion] The research provides theoretical basis for satisfying the demands of different industries for α-amylase with different characteristics.

Vanadium recovery from stone coal through roasting and flotation

A new process for vanadium recovery from stone coal by roasting-flotation was investigated based on the mineralogy. The process comprised four key steps： decarburization, preferential grinding, desliming and flotation. In the decarburization stage, roasting at 550 ℃ effectively avoided the negative effect of the carbonaceous materials in raw ore and generation of free CaO from calcite decomposition during roasting. Through preferential grinding, the high acid-consuming minerals were enriched in the middle fractions, while mica was enriched in the fine and coarse fractions. Through flotation, the final concentrate can be obtained with V2O5 grade of 1.07% and recovery of 83.30%. Moreover, the vanadium leaching rate of the final concentrate increased 13.53% compared to that of the feed. The results reveal that the decarburization by roasting at 550 ℃ is feasible and has little negative impact on mica flotation, and vanadium recovery from stone coal is conducive to reducing handling quantity, acid consumption and production cost.

Electrochemical behavior of galena and jamesonite flotation in high alkaline pulp

In order to effectively separate galena and jamesonite and improve the recovery during the mixing flotation, the interaction mechanisms between the minerals and the collector of diethyl dithiocarbamate （DDTC） were investigated. Single mineral flotation test was organized to research the effect of pulp pH value on the flotation behavior of galena and jamesonite. Electrochemistry property of the interaction of these two minerals with DDTC was investigated by cyclic voltammetry and Tafel tests. Flotation test shows that the recovery of jamesonite in high alkaline pulp is strongly depressed by lime （Ca（OH）2）. The cyclic voltammetry and Tafel tests results show that the interaction between galena and DDTC is an electrochemical process. High pH value has little influence on the interaction between galena and DDTC, while it has great effect on jamesonite due to self-oxidation and specific adsorption of OH^- and CaOH^＋ on jamesonite surface. Non-electroactive hydroxyl compound and low-electroconductive calcium compounds cover the surface of jamesonite, which impedes electron transfer and DDTC adsorption, thus leads to very low floatability of jamesonite.

Enantio-selective preparation of (S)-1-phenylethanol by a novel marine GDSL lipase MT6 with reverse stereo-selectivity

We previously functionally characterized a novel marine microbial GDSL lipase MT6 and identified that the stereo-selectivity of MT6 was opposite to that of other common lipases in trans-esterification reactions.Herein,we have investigated the use of MT6 in stereo-selective biocatalysis through direct hydrolysis reactions.Notably,the stereo-selectivity of MT6 was also demonstrated to be opposite to that of other common lipases in hydrolysis reactions.Parameters,including temperature,organic co-solvents,pH,ionic strength,catalyst loading,substrate concentration,and reaction time,affecting the enzymatic resolution of racemic 1-phenylethyl acetate were further investigated,with the e.e.of the final（S）-l-Phenylethanol product and the conversion being 97%and 28.5%,respectively,after process optimization.The lengths of side chains of 1-phenylethyl esters greatly affected the stereo-selectivity and conversion during kinetic resolutions.MT6 is a novel marine microbial GDSL lipase exhibiting opposite stereo-selectivities than other common lipases in both trans-esterification reactions and hydrolysis reactions.

Effect of silicon on phase selection of ternary compounds during solidification of ZA84 magnesium alloy

Effect of silicon on the phase selection between τ phase（Mg32（Al,Zn）49） and φ phase（Al2Mg5Zn2） in ZA84（Mg-8Zn-4Al-0.3Mn） magnesium alloy produced by steel mold cast was studied using X-ray diffractometer,scanning electron microscope and differential scanning calorimeter.The results show that with increasing Si addition in ZA84 alloy,the liquidus temperatures of the alloys and the solidification temperature ranges decrease.The ternary compound in ZA84 alloy is mainly τ phase and a little φ phase.When adding Si to ZA84 alloy,the preferential precipitation sequence of the ternary compounds changes,φ phase preferentially forms,whereas τ phase is suppressed.The solidification kinetics study of phase selection indicates that there is a critical degree of undercooling of the melt.If the undercooling exceeds the critical degree,τ phase preferentially forms while φ phase is suppressed;otherwise,φ phase preferentially forms while τ phase is suppressed.

顾千里在《昭明文选》研究领域的贡献

顾千里作为清代乾隆、嘉庆间的著名学者,在《昭明文选》研究领域有两方面的卓越贡献。一是制订了一份完整而全面的“文选学”研究提纲,二是与彭兆荪共同校勘尤本《文选》,并且撰成《文选考异》这一选学校勘名书,为清代以来在选学界影响甚巨的胡刻本《昭明文选》的刊印奠定了坚实的基础。

Integrity of Four Theories on Natural Selection Unit

[Objective] The aim was to study the internal relationship of the four theories on natural selection unit. [Method] The value field of fitness of heterozygote was investigated by constructing mathematical models, to clarify the internal relations of the four theories on natural selection unit. [Result] According to mathematical modes constructed in the study, only the mutated genes meet the requirements of natural selection on heterozygous and homozygous aspects, as well as show high fitness in heterozygous condition, could the mutated genes be kept, giving consideration to both individual and population adaptation. Thus, this methodology theoretically inte- grates the theories of individual selection, collective selection, and genetic selection as well as Kimura＇s neutral theory of health information. [Conclusion] The result of this study suggested that the four theories on natural selection unit can co-exist, and share common premises.

Isolating and Screening of Effective Decomposing Strain of Silkworm Chrysalis Protein and Study on Parts of Its Enzymatic Properties

[Objective] The research aimed to obtain an effectively-decomposing strain of silkworm chrysalis protein and discuss its enzymatic properties.[Method] The effectively-decomposing bacteria of protein was isolated from the decayed silkworm chrysalis by using dilution plate and its enzymatic properties were tested after primary screening and second screening.The enzyme activity was determined and the intermediate and small molecule protein content in silkworm chrysalis was measured after solid-state fermentati...

《文选集评》成书考

《文选集评》在《文选》评点史上有重要地位,要理清《文选》评点史脉络,整体把握明清《文选》评点状况,于光华《文选集评》是其中的关键。但现今学术界对《文选集评》的研究并不多,与其地位不成正比。论文以《文选集评》为研究对象,通过对《文选集评》成书进行考证分析,理清其成书过程以及于氏所受江苏地区“选学”背景和家学影响,探求《文选集评》成书的综合影响因素,以期对《文选集评》的其他研究打下坚实的文献基础。

Heuristic feature selection method for clustering

In order to enable clustering to be done under a lower dimension, a new feature selection method for clustering is proposed. This method has three steps which are all carried out in a wrapper framework. First, all the original features are ranked according to their importance. An evaluation function E（f） used to evaluate the importance of a feature is introduced. Secondly, the set of important features is selected sequentially. Finally, the possible redundant features are removed from the important feature subset. Because the features are selected sequentially, it is not necessary to search through the large feature subset space, thus the efficiency can be improved. Experimental results show that the set of important features for clustering can be found and those unimportant features or features that may hinder the clustering task will be discarded by this method.

Pd/ZnO catalysts with different origins for high chemoselectivity in acetylene semi-hydrogenation

The heterogeneity of active sites is the main obstacle for selectivity control in heterogeneous catalysis.Single atom catalysts（SACs） with homogeneous isolated active sites are highly desired in chemoselective transformations. In this work, a Pd1/ZnO catalyst with single‐atom dispersion of Pd active sites was achieved by decreasing the Pd loading and reducing the sample at a relatively low temperature. The Pd1/ZnO SAC exhibited excellent catalytic performance in the chemoselective hydrogenation of acetylene with comparable chemoselectivity to that of PdZn intermetallic catalysts and a greatly enhanced utilization of Pd metal. Such unusual behaviors of the Pd1/ZnO SAC in acetylene semi‐hydrogenation were ascribed to the high‐valent single Pd active sites, which could promote electrostatic interactions with acetylene but restrain undesired ethylene hydrogenation via the spatial restrictions of σ‐chemical bonding toward ethylene.

Study on college English elective courses

College English Curriculum Requirements poses a great challenge for college English teaching. One way to deal with the status quo is to offer selective courses to non-English majors. This article gives an early probe into the rationale on a new course-designing practice as well as a detailed introduction to an illustrative course. As proved, the attempt to practice selective courses is feasible and effective for individualized teaching and integrated language competence cultivation.

Metal–organic-framework-based catalysts for hydrogenation reactions

Metal-organic-framework （MOF）-based materials with novel physicochemical properties have emerged as promising catalysts for various hydrogenation reactions. In addition to metal clusters and multifunctional organic ligands, MOF-based catalysts can incorporate other functional species, and thus provide various active sites for hydrogenation processes. The structural properties of the catalysts play significant roles in enhancing the interactions among the reactants, products, and catalytic sites, which can be rationally designed. Because of the synergistic effects between the ac-tive sites and the structural properties, MOF-based catalysts can achieve higher activities and selec- tivities in hydrogenation reactions than can be obtained using traditional heterogeneous catalysts. This review provides an overview of recent developments in MOF-based catalysts in the hydro-genation of alkenes, alkynes, nitroarenes, cinnamaldehyde, furfural, benzene, and other compounds. Strategies for improving the catalytic performances of MOF-based catalysts are discussed as well as the different active sites and structural properties of the catalysts.