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Zeolite－Catalyzed　Friedel－Crafts　Acylation　of　Aromatics．Ⅳ．Nature　of　the　Active　Sites　of　Zeolites

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Chinese Chemical Letters 1996年第9期7卷 841-844页

作者： Yu Dao MA Qi Long WANG Wei JIANG Be Jun ZUO and Qin QIU(department of Chemistry,shandong university,jinan 250100.)(department of Environmental Engineering, shandong university,jinan 250100.) department of Chemistry Shandong University Jinan 250100 Dept. of Environmental Engineering Shandong University Jinan 250100

For zeolite-catalyzed Friedel-Crafts acylation of aromatic rings,the Lewis acid sites were found to be active;while the Bronsted acid sites with moderate strength were found to be inactive.

关键词： Nature Aromatics the Active

EDGE RECONSTRUCTION OF PLANAR GRAPHS WITH MINIMUM DEGREE AT LEAST THREE-(Ⅰ)

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Systems Science and Mathematical Sciences 1993年第4期6卷 376-382页

作者： FAN Hongbing department of Mathematics, shandong university, jinan 250100, china 山东大学山东济南

The object of this series of papers is to show that every planar graph ofminimum degree at least 3 is edge reconstructible. In this paper, we prove that such agraph with connectivity 2 is edge reconstructible.

关键词： Reconstruction isomorphism planar graph

Note on the number of integral ideals in Galois extensions

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Science china Mathematics 2010年第9期53卷 2417-2424页

作者： L GuangShi1,& WANG YongHui2 1School of Mathematics,shandong university,jinan 250100,china 2department of Mathematics,Capital Normal university,Beijing 100048,china School of Mathematics Shandong University Jinan China department of Mathematics Capital Normal University Beijing China

Let K be an algebraic number field of finite degree over the rational filed *** ak be the number of integral ideals in K with norm *** this paper we study the l-th integral power sum of ak,i.e.,∑k≤ x akl(l = 2,3,...).We are able to improve the classical result of Chandrasekharan and *** an application we consider the number of solutions of polynomial congruences.

关键词： Dedekind zeta-function integral ideal congruences

Nd: Sr5 (PO4 )3 F Crystal Laser Characteristics Using GaAs as Passive Q-switch

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Chinese Journal of Lasers 2000年第2期9卷 107-110页

作者： LI Ping ,WANG Qingpu, ZHANG Xinyu, ZHAO Shenzi, GAO Da (Optics department, shandong university, jinan 250100, china ) LIU Xunmin ,SUN Lianke ,ZHANG Shaojun, HUANG Bobiao (Institute of Crystal Materials, shandong university, jinan 250100, china ) LIN Benfu 山东大学山东济南淄博电子材料厂山东淄博

It is investigated the properties of a diode-pumped Nd: Sr5 （PO4）3 F laser that is passively Q- switched by a thin, single crystal GaAs wafer. The short high-peak-power pulses of the laser have been obtained. The pulse energies, pulse widths and pulse repetition rates for different conditions have been measured and the experimental results show that GaAs is an excellent passive Q- switch of the diode-pumped Nd: Sr5（PO4）3F lasers.

关键词： Nd:Sr5(PO4)3 F GaAs diode-pumped lasers Q-switch

A　Study　on　the　Simultaneous　Determination　of　Copper　and　Tin　in　the　Presence　of　Lead

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Chinese Chemical Letters 1996年第9期7卷 818-819页

作者： Xiao Li ZHANG Chi Min DU(department of Chemistry shandong university, jinan 250100) department of Chemistry Shandong University Jinan 250100

A very sensitive electrochemical procedure for trace determination of copper and tin in the presence of lead using cathodic adsorption voltammetry is *** complex of copper,tin with salicylfluorone (SAF) is adsorbed on the hanging mercury drop electrode (HMDE) and the reduction current of the accumulated complex is measured by *** method achieves the simultaneous determination of copper and tin,and has been applied to determine canned *** stripping voltarnmetry (ASV)is an effeCtive electroanajytital technique for themeasurement Of trace metal *** there are serious interferences due to overlapping strippingpeak and forming of intermetamc complex in complicated *** results are usUally notsatisfaCtory. The dffeulty of simultaneous determination Of copper and tin in the presence of leadis the strong tendency of tin (IV ) species to hydrolyZO and polwnerise as well as the overlap ofthe stripping Peaks of tin and lead by anodic stripping voltarnmetry at mercury electrodes. Inaddition, tin and copper easily created into intermetailic complex on HMDE and the tin peak isrestrained by copper;it is very dimcult to determine them,individually or *** approaches have been employed to improve the selectivity of tin measurement bystripping *** include prior separation['J, flow or medium--exchange schemes[23 orthe addtion Of surfactants' L3) We have determined Zr[4), Ga[sj, V['J, Sb[7) etc,by Cathodicstripping VOltammetry (csv) using nuorone claSs ligand as complexing *** this paper, wereport a hashly sensitive and selective stripping approach for sdriultaneous determination of copperand tin in the presence of lead' The method has been used to sampled of canned food.

关键词： Determination Tin

Hua's Theorem on Prime Squares in Short Intervals

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Acta Mathematica Sinica,English Series 2000年第4期16卷 669-690页

作者： Jianya Liu Tao Zhan department of Mathematics. shandong university. jinan 250100. P. R. china department of Mathematics Shandong University Jinan 250100 P. R. China

It is proved that every large integer N≡5（mod24）can be written as N=p12+…+p52 with each prime pj satisfying |pJ-（N/5|）1/2≤N11/23.This gives a short interval version of Hua’s theorem on the quadratic Waring-Gol... 详细信息

关键词： Waring-Goldbach problem Hua’s theorem Prime Circle method

ZEOLITE－CATALYZED　FRIEDEL－CRAFTS　ACYLATION　OF　AROMATICS：I》．SYNTHESIS　OF　4－ACYL　ANISOLE　WITH　A　HY　CATALYST

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Chinese Chemical Letters 1996年第2期7卷 99-102页

作者： Qi Long WANG Yu Dao MA Xing Dong JI Hao YAN(department of Chemistry,shandong university,jinan, 250100)and Qin QIU(department of Environmental Engineering,shandong university.,jinan, 250100) department of Chemistry Shandong University Jinan 250100 China Dept. of Environmental Engineering Shandong University Jinan 250100 China

A series of aromatic ketones 4-acyl anisole were synthesized with high yield by using carboxylic acids as acylating agents and a HY zeolite as catalyst.

关键词： HY CATALYST WITH ANISOLE ACYLATION ACYL

The Synthesis, Photoconductivity, Photoinduced Charge Transfer, and Other Properties of HEC-TCNQ

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Chinese Chemical Letters 1997年第1期8卷 75-78页

作者： Qi FANG Hong LEI Dong XU Duo Rong YUAN(Institute of Crystal Materials, shandong university, jinan 250100department of Electronic Engineering, shandong university, jinan 250100) Institute of Crystal Materials Shandong University Jinan 250100 China department of Electronic Engineering Shandong University Jinan 250100 China

The donor-acceptor complex HEC-TCNQ (HEC = 9-hydroxyethylcarbazole; TCNQ = tetracyanoquinodimethane) has been synthesized. Under the illumination of Ar+ laser, the photoinduced charge transfer salt HEC(+)TCNQ(-) can b... 详细信息

关键词： HEC The Synthesis Photoconductivity Photoinduced Charge Transfer and Other Properties of HEC-TCNQ

Sustainable Intensification and Large-scale Operation of Cultivated Land Use at the Farmers’ Scale:A Case Study of shandong Province,china

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Chinese Geographical Science 2024年第1期34卷 149-167页

作者： LI Li LYU Xiao ZHANG Anlu NIU shandong PENG Wenlong School of Public Administration Huazhong Agricultural UniversityWuhan430070China department of Geography University of ZurichZurich8057Switzerland School of Humanities and Law Northeastern UniversityShenyang110169China School of Geography and Tourism Qufu Normal UniversityRizhao276800China

Sustainable intensification of cultivated land use(SICLU) and large-scale operations(LSO) are widely acknowledged strategies for enhancing agricultural ***,the existing literature has faced challenges in precisely defining SICLU and constructing comprehensive indicators,which has hindered the exploration of factors influencing LSO within the SICLU *** address this gap,we integrated self-efficacy theory into the design of an index framework for evaluating *** subsequently employed econometric models to analyze the significant factors that impact *** findings reveal that SICLU can be divided into four key dimensions:intensive management,efficient output,resource conservation,and ecological environment ***,it is crucial to incorporate belief-based cognitive factors into the index system,as farmers’ understanding of fertilizer and pesticide application significantly influences their willingness to engage in ***,we identify grain market turnover as the most influential factor in promoting LSO,with single-factor contribution rates reaching 70.9% for cultivated land transfer willingness and 62.5% for the total planting ***,unlike irrigation and agricultural machinery inputs,increased labor inputs correspond to larger planting areas for *** trend may be attributed to reduced labor availability because of rural labor migration,whereas the reduction in irrigation and agricultural input is contingent on innovations in production practices and the transfer of cultivated land management ***,SICLU dynamically influences LSO,with each index related to SICLU having an optimal range that fosters *** insights offer valuable guidance for policymakers,emphasizing farmers as their central focus,with the adjustment of input and output factors as a means to achieve LSO as the ultimate *** conclusion,we propose research avenues for further enriching the SICLU framework to ensur

关键词： sustainable intensification of cultivated land use(SICLU) self-efficacy status quo bias input and output Boosted Regression Tree willingness to transfer cultivated land cultivated land planting areas shandong,china