我国区域绿色技术创新效率的分类测度和提升模式研究——基于非期望产出的SBM-SupSBM模型

本文首先运用考虑非期望产出的SBM-SupSBM模型估计我国各省市绿色技术创新效率并进行分类:稳定上升类、平稳类、大幅度波动类以及下降类。之后从企业内部和外部两方面对绿色技术创新效率提升的影响因素提出假设,着重考虑大幅度波动类别省份的效率提升。运用面板数据模型各影响因素进行验证,结论显示:企业规模对绿色技术创新效率波动较大的省份起到显著的抑制作用,环境规制和技术进步对绿色技术创新效率波动较大的省份作用不明显。针对分析结果,提出结论:在提升绿色技术创新效率的过程中,应注重企业规模和技术进步的协同作用,以及技术的开放程度。     

Structure,trend and prospect of operational research: a scientific analysis for publications from 1952 to 2020 included in Web of Science database

As an important research direction, operational research (OR) has always attracted scholars worldwide. We study the structure, trend and prospect in the OR field by conducting a bibliometric analysis of publications in the period of 1952–2020, which are included in the Web of Science (WoS) database. Using three effective bibliometric tools, namely, VOS viewer, CiteSpace, and Bibliometrix, a total of 5,353 publications were retrieved to show clear visual results using a series of scientific analyses. First, a performance analysis revealed the basic characteristics of publications considering the type distribution, annual trend, quantity and quality. Then, a cooperation analysis presented the influential countries/regions and showed the relationships among countries/regions, institutions and authors during different periods based on bibliometric indicators and co-authorship networks. Moreover, a keyword analysis was conducted to investigate the hot topics and development of the OR field, using co-occurrence analysis, timeline view analysis and evolution analysis. Finally, we discussed the implications and limitations, and summarized the main findings. This study hopes to provide important and valuable references for future research on the OR field.

     

Reaction-diffusion model for combustion with fuel consumption: II. Robin boundary conditions

A model, derived in a previous paper, for the reaction betweena gaseous oxidant and a solid porous fuel is analysed furtherfor general Robin boundary conditions. Numerical solutions areobtained and the effects of varying the dimensionless parameters,particularly the Frank-Kamenetskii parameter and the Lewisnumber L, are discussed in detail and compared with resultsobtained previously when Dirichlet boundary conditions are applied.Analytic solutions are obtained for the small-time developmentand for large values of . This latter solution shows the existenceof a propagating reaction-diffusion burning wave, and has featureswhich are qualitatively different to those derived earlier.     

Tandem mass spectrum of a farnesyl transferase inhibitor--gas-phase rearrangements involving imidazole

Compound 1 (1-(3-chlorophenyl)-4-[1-(4-cyanobenzyl)imidazolylmethyl]-2-piperazinone hydrochloride) is a farnesyl transferase inhibitor intended for treatment of cancer. A detailed analysis of the electrospray ionization mass spectrometry and tandem mass spectrometry data of protonated 1 shows that in the gas phase, upon collision-induced dissociation, this ion undergoes complicated rearrangement and fragmentation. These processes include a novel two-step rearrangement. The first step involves a gas-phase intramolecular S(N)2 reaction that forms an intermediate. The second step consists of three competitive rearrangement/fragmentation pathways of the intermediate, giving rise to protonated 2, protonated methylene-imidazole, and a distonic methylimidazole radical cation. Deuterated 1 was studied under the same experimental conditions, and the results strongly support the proposed two-step rearrangement process. It is noted that the unique structure of 1, especially the imidazole ring of 1, plays a critical role in the rearrangement of protonated 1.     

A New Chemiluminescence Amplification Reaction for the Determination of HRP and Labelled HRP

A new chemiluminescence amplification reaction has been developed, which is on the coupling of the oxidation of Eosin by hydrogen peroxide under the catalysis of HRP at pH 3. 5 to the chemiluminescent reaction of luminol and hydrogen peroxide catalyzed by HRP at pH 10 to measure the activity of HRP and labelled-HRP. The detection limit of HRP is 10-10 g/mL. The lowest dilution ratio of HBsAb-HRP is 1 : 1. 8×102 and 1 : 106 for the direct method and coupled method respectively.     

N,N-二甲基甲酰胺中电沉积制备镁镍储氢合金

采用恒电位沉积法, 选用适宜的添加剂和络合剂, 成功地从N,N-二甲基甲酰胺(DMF)中沉积出致密的黑色Mg-Ni储氢合金膜. 并初步探讨了其共沉积机理. XRD显示沉积层中含有非晶态Mg-Ni相和微晶态Mg相. SEM图及相应能谱图分析表明合金颗粒以团聚状态存在, 合金成分不是很均匀. AAS分析表明沉积合金中Mg的原子摩尔分数达27.3%. LAND电池测试系统测得所镀合金膜的放电比容量最高为172.4 mAh/g.     

Simultaneous determination of noradrenaline and dopamine in Portulaca oleracea L. by capillary zone electrophoresis

A simple and rapid capillary electrophoretic method was developed for the simultaneous determination of noradrenaline (NA) and dopamine (DA) in Portulaca oleracea L. The buffer solution used in this method was 40 mM tris (hydroxymethyl) aminomethane (Tris)-H3PO4 at pH 2.00 containing 15% methanol. The effects of pH value, organic modifier, and applied voltage were investigated. The linear ranges of NA and DA were 0.5-100 microg/mL (r=0.9952) and 6.25-200 microg/mL (r=0.9992), respectively. The relative standard deviations of the corrected peak area were 6.73% and 4.26%, respectively. NA and DA in Portulaca oleracea L. were simultaneous determined successfully within 5.6 min. In this way, the contents of NA and DA in different parts (stem, leaves, and seeds) of P. oleracea L. and in different extracts of leaves with different solvents (distilled water, 50% methanol, and methanol) were studied.     

INTRAPARTICLE DIFFUSION EFFECTS IN FISCHER-TROPSCH SYNTHESIS Ⅰ. MODELING OF DIFFUSION AND REACTION

IntroductionCatal}ticrcactionsaffcctcdb}'diffosionaIlimitationincatal}'stporcshavcbccnextensive1}dcaltx`ithinlit.rat.rcll~5I.Scvcraltcchniqucsonthcspccialcase0fFischcr-Tropschs}'nthcsis(FTS)t\crcapplicdtocxplorcthebchaviorofthiscatal}ticrcactionundercxpcrimcntalandopcrationaIconditionsI3~5l.It`"ouldbeofvaluctoindicatchcrcthatthcseinvcstigationsx"ercmainl}'bascdonthesimplcstkineticsofthcfirstordcrinH2proposedbyAndersonl6]attheearIystages.However-thesetboents,striCtlyspeaking,areinvalidfor…     

氢化物发生-冷原子吸收光谱法测定化妆品中汞

介绍用氢化物发生-冷原子吸收光谱法在重铬酸钾-硝酸溶液存在下测定化妆品中汞的含量。方法空白值低、灵敏、准确、精密度好，特别适合于化妆品中汞的测定。     

Duality and intersection theory in complex manifolds. I

We introduce the concept of a twisting cochain and a twisted complex associated to a coherent sheaf. For sheaves of submanifolds these twisted complexes are used to construct on cochain level the Grothendieck theory of dual class and Gysin map. These explicit constructions give, for instance, a local formula for dual class of higher codimensional submanifolds. We prove a refined version of the Hirzebruch Riemann Roch using such local formulas. We also prove a theorem on when global analytic intersection classes can be computed from first order geometric data. This theory will be used to prove the Holomorphic Lefschetz formula (in Part II) and the Hirzebruch Riemann Roch for analytic coherent sheaves.The first author is supported in part by NSF grants GP-36418X1 and MCS 76-08478. The second by MCS 75-07986 and Sonderforschungsbereich Theoretische Mathematik at Bonn University