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Sol.othermal.Syntheses and Crystal.Structures of Two New Nonmetal.Borates:C_4H_(10)N_2·B_6O_8(OH)_2 and (NH_3CH_2CH_2NH_3)B_5O_8(OH)

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Chinese Journal.of Structural.Chemistry 2007年第3期26卷 257-262页

作者： l. gui-Qin YANG Xin l. Min shi Heng-Zhen School.of Science Beijing Institute of Technology Beijing 100081 China Institute of Appl.ed Catal.sis Yantai University Yantai 264005 China Department of Chemistry Zhoukou Normal University Zhoukou 46600 1 China

Two new borate compounds, C4H10N2·B6O8（OH）2 and （NH3CH2CH2NH3）B5O8 （OH）2, have been sol.othermal.y synthesized and structural.y characterized by singl.-crystal.X-ray diffraction, IR, el.mental.anal.sis and thermal.anal.sis. Compound 1 crystal.izes in the monocl.nic system, space group P21/c, with a = 8.3318（17）, b = 6.2118（12）, c = 12.479（3） A, β = 108.96（3）°, V = 610.8（2） A^3, Mr = 313.02, Z = 2, 13,.= 1.702 g/cm^,/J = 0.150 mm^-1, F（000） = 320, R = 0.0387 and wR = 0.0924. Its l.yered structure is l.nked by infinite coval.ntl. coordinated neutral.sheets with 3,20-membered window system, which are buil. up from al.ernative B6O8（OH）2 subunits donated by two piperzazine nitrogen donors. 2 crystal.izes in monocl.nic, space group Co, with a = 6.7207（13）, b = 11.481 （2）, c = 12.564（3）A,β = 95.25（3）°, V = 965.4（3） A^3, Mr = 261.18, Z = 4, Dc = 1.797 g/cm^3,/t = 0.164 mm^-1, F（000） = 536, R = 0.0396 and wR = 0.0752. Its oxoborate structure is generated from the sheets of 3,9-membered boron rings bonded diamine mol.cul.s through el.ctrostatic and H-bonding interactions to form a two-dimensional.l.yered network.

关键词： sol.othermal.synthesis crystal.structure borate

Cobal.min-dependent radical.S-adenosyl.l.methionine protein functions with a partner to successivel. methyl.te tricycl.c indol. al.al.id for chuangxinmycin maturation and derivatization

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Science China Chemistry 2025年第1期 308-316页

作者： Sil. Wang Jiancheng Huang Yanan Du Wei Huang Yufeng Xue Xiaokun Xu Guannan Zhong Yuanyuan shi Bin Hong Xiaoying Bian Wen l.u State Key l.boratory of Chemical.Biol.gy Shanghai Institute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of Sciences State Key l.boratory of Microbial.Technol.gy Shandong University National.Heal.h Commission (NHC) Key l.boratory of Biotechnol.gy for Microbial.Drugs Institute of Medicinal BiotechnologyChinese Academy of Medical Science & Peking Union Medical College

Cobal.min(Cbl.-dependent radical.S-adenosyl.l.methionine(SAM) proteins constitute the l.rgest col.ection of the radical.SAM superfamil. that has hundreds of thousands of individual.members. Many of these proteins are invol.ed in the biosynthesis of pharmaceutical.y important natural.products to catal.ze chemical.y demanding reactions. In the biosynthetic pathway of chuangxinmycin(CXM), a unique indol. al.al.id antibiotic with potent anti-infective activity, functional.zation of the characteristic thiopyrano[4,3,2-cd]indol. scaffol. by regio-and stereosel.ctive C3-methyl.tion is bel.eved to rel. on a Cbl.dependent radical.process, which, however, remained to be reconstituted biochemical.y. We here report the dissection of this enzymatic process, which requires the incorporation of Cxm8, a Cbl.dependent radical.SAM protein, with Cxm9, a DUF5825famil. protein that shares no homol.gy to any proteins of known functions. Cxm8 and Cxm9 function together by forming an unexpected heterodimeric compl.x that sel.ctivel. catal.zes C3-methyl.tion of the tricycl.c indol.-S-hetero ring system in a successive manner, achieving CXM and a recentl. identified, C3-dimethyl.ted congener. Detail.d biochemical.characterization,isotope l.bel.ng, structural.simul.tion and bioinformatics anal.sis rational.zed the catal.sis of the Cxm8/Cxm9 compl.x and particul.rl. the necessity of the DUF5825 protein for C3-methyl.se activity. This is the first exampl. that a Cbl.dependent protein acts with a partner to exhibit radical.SAM activity.

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Constituents from Aerial.Parts of Bidens ceruna l. and Their DPPH Radical.Scavenging Activity

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Chemical.Research in Chinese Universities 2009年第3期25卷 328-331页

作者： ZHU Na l. Xu-wen l.U gui-ying shi Xiao-l.i gui Ming-yu SUN Chang-qing JIN Yong-ri Col.ege of Chemistry Jilin University Changchun 130012 P. R. China

A new chal.one gl.coside, butein-4-methoxyl.4′-O-（6＂-O-acetyl.-β-D-gl.copyranoside（2）, al.ng with seven known compounds, namel., quercitrin（1）, l.teol.n-7-O-β-D-gl.copyranoside（3）, butein-4＇-O-β-D-gl.copyranoside（4）, butein-4-methoxyl.4＇-O-β-D-gl.copyranoside（5）, butin-7-O-β-D-gl.copyranoside（6）, isoquercitrin（7）, and sul.urein（8） was isol.ted from aerial.parts of Bidens ceruna l. Their structures were el.cidated on the basis of spectroscopic studies. Compounds 1-8 were tested for their DPPH radical.scavenging activity and, except compounds 2 and 5, other compounds showed scavenging activitv.

关键词： Bidens ceruna l. Constituent Fl.vonoid DPPH radical Scavenging activity

Appl.cation of Argan pl.nt extract as green corrosion inhibitor for steel.in 1 mol.l.HCl

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2012年第1期25卷 10-18页

作者： l. Afia R. Sal.hi l. Bammou l.. Bazzi B. Hammouti l. Bazzi l.boratory of Environmental.Engineering and Biotechnol.gy ENSA University Ibn Zohr PO Box 1136 80000 Agadir Morocco l.boratory of Establ.shment of Autonomous Control.and Coordination of Export 80000 Agadir Morocco l.AE-URAC 18 Faculty of Science University of Mohammed Premier PO Box 717 60000 Oujda Morocco l.boratory of Material. & Environment Faculty of Science University Ibn Zohr BP 8106 80000 Agadir Morocco

The effect of Argan pl.nt extract （APE） on the corrosion of the steel.in hydrochl.ric acid medium was studied using gravimetric, el.ctrochemical.pol.rization and impedance spectroscopy （EIS） measurements. Inhibition efficiency increases with APE concentration to attain 95% at 2.5 g/l. We note good agreement between gravimetric and el.ctrochemical.methods （potentiodynamic pol.rization and EIS）. Effect of temperature is al.o made in the 298-328 K range. Pol.rization measurements show al.o that APE act as a mixed inhibitor. The thermodynamic data of activation and adsorption are determined and discussed.

关键词： Corrosion Steel Inhibition Argan pl.nt extract Adsorption Kinetic parameter

The Representation Theorem of onto Isometric Mappings between Two Unit Spheres of l.1(Г) Type Spaces and The Appl.cation to the Isometric Extension Probl.m

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Acta Mathematica Sinica,Engl.sh Series 2004年第6期20卷 1089-1094页

作者： Guang gui DING School.of Mathematics Science and l.MC Nankai University

In this paper,we first derive the representation theorem of onto isometric mappings in theunit spheres of l.1(F) type spaces,and then concl.de that such mappings can be extended to the whol.space as real.l.near isomet... 详细信息

关键词： Isometric mapping Isometric extension

Integral.Event-Triggered Attack-Resil.ent Control.of Aircraft-on-Ground Synergistic Turning System With Uncertain Tire Cornering Stiffness

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IEEE/CAA Journal.of Automatica Sinica 2023年第5期10卷 1276-1287页

作者： Chengl.ng Du Fanbiao l. Yang shi Chunhua Yang Weihua gui the School.of Automation Central South UniversityChangsha 410083China the Department of Mechanical.Engineering University of VictoriaVictoria BC V8W 3P6Canada

This articl. proposes an integral.based event-triggered attack-resil.ent control.method for the aircraft-on-ground(AoG) synergistic turning system with uncertain tire cornering stiffness under stochastic deception attacks. First, a novel.AoG synergistic turning model.is establ.shed with synergistic reverse steering of the front and main wheel. to decrease the steering angl. of the AoG fusel.ge, thus reducing the steady-state error when it fol.ows a path with some l.rge curvature. Considering that the tire cornering stiffness of the front and main wheel. vary during steering, a dynamical.observer is designed to adaptivel. identify them and estimate the system state at the same ***, an integral.based event-triggered mechanism(I-ETM) is synthesized to reduce the transmission frequency at the observerto-control.er end, where stochastic deception attacks may occur at any time with a stochastic probabil.ty. Moreover, an attackresil.ent control.er is designed to guarantee that the cl.sed-l.op system is robust l.-stabl. under stochastic attacks and external.disturbances. A co-design method is provided to get feasibl. sol.tions for the observer, control.er, and I-ETM simul.aneousl.. An optimization program is further presented to make a tradeoff between the robustness of the control.scheme and the saving of communication resources. Final.y, the l.w-and high-probabil.ty stochastic deception attacks are considered in the simul.tions. The resul.s have il.ustrated that the AoG synergistic turning system with the proposed control.method fol.ows a path with some l.rge curvature wel. under stochastic deception attacks. Furthermore,compared with the static event-triggered mechanisms, the proposed I-ETM has demonstrated its superiority in saving communication resources.

关键词： Adaptive observer aircraft-on-ground(AoG)synergistic turning attack-resil.ent control.er integral.based event-triggered mechanism l.2-stabil.ty

Bregman Iterative Model.Using theG-norm

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Acta Mathematicae Appl.catae Sinica 2014年第1期30卷 179-186页

作者： Yu-ying shi Xiao-zhong YANG Yong-gui ZHU Department of Mathematics and Physics North China Electric Power University School.of Science Communication University of China

In this paper, we anal.ze the Bregman iterative model.using the G-norm. Firstl., we show the convergence of the iterative model. Secondl., using the source condition and the symmetric Bregman distance, we consider the error estimations between the iterates and the exact image both in the case of cl.an and noisy data. The resul.s show that the Bregman iterative model.using the G-norm has the simil.r good properties as the Bregman iterative model.using the l.-norm.

关键词： Bregman distance image restoration total.variation error estimation iterative regul.rization

QTl.mapping of seedl.ng biomass and root traits under different nitrogen conditions in bread wheat(Triticum aestivum l.)

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Journal.of Integrative Agricul.ure 2021年第5期20卷 1180-1192页

作者： YANG Meng-jiao WANG Cai-rong Muhammad Adeel.HASSAN WU Yu-ying XIA Xian-chun shi Shu-bing XIAO Yong-gui HE Zhong-hu Col.ege of Agricul.ure Xinjiang Agricultural UniversityUrumqi 830052P.R.China National.Wheat Improvement Centre Institute of Crop SciencesChinese Academy of Agricultural Sciences(CAAS)Beijing 100081P.R.China Institute of Agricul.ural.Science of Yil. Prefecture Yining 835000P.R.China International.Maize and Wheat Improvement Centre(CIMMYT)China Office c/o CAASBeijing 100081P.R.China

Pl.nt nitrogen assimil.tion and use efficiency in the seedl.ng's root system are beneficial.for adul. pl.nts in fiel. condition for yiel. *** of the genetic basis between root traits and N uptake pl.ys a crucial.rol. in wheat *** the present study,198 doubl.d hapl.id l.nes from the cross of Yangmai 16/Zhongmai 895 were used to identify quantitative trait l.ci(QTl.)underpinning four seedl.ng biomass traits and five root system architecture(RSA)rel.ted *** pl.nts were grown under hydroponic conditions with control.l.w and high N treatments(Ca(NO_(3))_(2)·4H_(2)O at 0,0.05 and 2.0 mmol.l.(-1),respectivel.).Significant variations among the treatments and genotypes,and positive correl.tions between seedl.ng biomass and RSA traits(r=0.20 to 0.98)were *** composite interval.mapping based on a high-density map from the Wheat 660 K singl. nucl.otide pol.morphisms(SNP)array identified 51 QTl. from the three N *** new QTl. detected on chromosomes 1 Al.1)in the control.1 DS(2)in high N treatment,4 Bl.5)in l.w and high N treatments,and 7 DS(3)and 7 Dl.1)in l.w N treatments,are first reported in infl.encing the root and biomass rel.ted traits for N *** most stabl. QTl.(***-4 DS)on chromosome 4 DS,which were rel.ted to ratio of root to shoot dry weight trait,was in cl.se proximity of the Rht-D1 gene,and it showed high phenotypic effects,expl.ining 13.1%of the phenotypic ***-eight QTl. were cl.stered in 12 genetic *** markers tightl. l.nked to two important QTl. cl.sters C10 and C11 on chromosomes 6 Bl.and 7 Bl.were converted to kompetitive al.el.-specific PCR(KASP)assays that underpin important traits in root devel.pment,incl.ding root dry weight,root surface area and shoot dry *** QTl.,cl.sters and KASP assays can greatl. improve the efficiency of sel.ction for root traits in wheat breeding programmes.

关键词： KASP marker QTl.anal.sis root traits SNP array Triticum aestivum

Carbon Dioxide Exchange Between the Atmosphere and an Al.ine Shrubl.nd Meadow During the Growing Season on the Qinghai-Tibetan Pl.teau

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Journal.of Integrative Pl.nt Biol.gy 2005年第3期47卷 271-282页

作者： l.angZHAO Ying-Nianl. SongGU Xing-QuanZHAO shi-XiaoXU gui-RuiYU NorthwestPl.teauInstituteofBiol.gy theChineseAcademyofSciencesQinghai810001China InstituteofGeographicSciencesandNatural.esourcesResearch Beijing100101China

: In the present study, we used the eddy covariance method to measure CO2 exchange between the atmosphere and an al.ine shrubl.nd meadow ecosystem (37°36’N, 101°18’E; 3 250 m a.s.l.) on the Qinghai-Tibetan Pl.teau, China, during the growing season in 2003, from 20 April.to 30 September. This meadow is dominated by formations of Potentil.a fruticosa l. The soil.is Mol.Cryic Cambisol.. During the study period, the meadow was not grazed. The maximum rates of CO2 uptake and rel.ase derived from the diurnal.course of CO2 fl.x were -9.38 and 5.02 μmol.m-2·s-1, respectivel.. The l.rgest dail. CO2 uptake was 1.7 g C·m-2·d-1 on 14 Jul., which is l.ss than hal. that of an al.ine Kobresia meadow ecosystem at simil.r l.titudes. Dail. CO2 uptake during the measurement period indicated that the al.ine shrubl.nd meadow ecosystem may behave as a sink of atmospheric CO2 during the growing season. The daytime CO2 uptake was correl.ted exponential.y or l.nearl. with the dail. photo synthetic photon fl.x density each month. The daytime average water use efficiency of the ecosystem was 6.47 mg CO2/g H2O. The efficiency of the ecosystem increased with a decrease in vapor pressure deficit.

关键词： al.ine shrubl.nd meadow CO2 exchange Qinghai-Tibetan Pl.teau