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Effects of reduced nitrogen and suitable soil moisture on wheat(Triticum aestivum L.) rhizosphere soil microbiological,biochemical properties and yield in the Huanghuai Plain,China

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Journal of Integrative Agriculture 2020年第1期19卷 234-250页

作者： ZHOU Su-mei zhang Man zhang Ke-ke YANG Xi-wen he De-xian YIN Jun WANG Chen-yang College of Agronomy Henan Agricultural UniversityZhengzhou 450002P.R.China Institute of Plant Nutrient and Environmental Resources Henan Academy of Agricultural SciencesZhengzhou 450002P.R.China

Soil management practices affect rhizosphere microorganisms and enzyme activities, which in turn influence soil ecosystem processes. The objective of this study was to explore the effects of different nitrogen application rates on wheat(Triticum aestivum L.) rhizosphere soil microorganisms and enzyme activities, and their temporal variations in relation to soil fertility under supplemental irrigation conditions in a fluvo-aquic region. For this, we established a split-plot experiment for two consecutive years(2014–2015 and 2015–2016) in the field with three levels of soil moisture: water deficit to no irrigation(W1), medium irrigation to(70±5)% of soil relative moisture after jointing stage(W2), and adequate irrigation to(80±5)% of soil relative moisture after jointing stage(W3);and three levels of nitrogen: 0 kg ha^–1(N1), 195 kg ha^–1(N2) and 270 kg ha^–1(N3). Results showed that irrigation and nitrogen application significantly increased rhizosphere microorganisms and enzyme activities. Soil microbiological properties showed different trends in response to N level;the highest values of bacteria, protease, catalase and phosphatase appeared in N2, while the highest levels of actinobacteria, fungi and urease were observed in N3. In addition, these items performed best under medium irrigation(W2) relative to W1 and W3;particularly the maximum microorganism(bacteria, actinobacteria and fungi) amounts appeared at W2, 5.37×10^7 and 6.35×10^7 CFUs g^–1 higher than those at W3 in 2014–2015 and 2015–2016, respectively;and these changes were similar in both growing seasons. Microbe-related parameters fluctuated over time but their seasonality did not hamper the irrigation and fertilization-induced effects. Further, the highest grain yields of 13 309.2 and 12 885.7 kg ha^–1 were both obtained at W2 N2 in 2014–2015 and 2015–2016, respectively. The selected properties, soil microorganisms and enzymes, were significantly correlated with wheat yield and proved to be valuable ind

关键词： suitable soil moisture nitrogen-reduction rhizosphere soil microorganisms rhizosphere soil enzyme activity winter wheat(Triticum aestivum L.)

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Allelic Variation at the TaZds-A1 Locus on Wheat Chromosome 2A and Development of a Functional Marker in Common Wheat

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Journal of Integrative Agriculture 2012年第7期11卷 1067-1074页

作者： DONG Chang-hai MA Zhi-ying XIA xian-chun zhang Li-ping he Zhong-hu College of Agronomy Agricultural University ofHebei Baoding 071001 P.R.China Institute of Crop Sciences National Wheat Improvement Center~The National Key Facility for Crop Gene Resources and Genetic Improvement Chinese Academy of Agricultural Sciences (CAAS) Beijing 100081 P.R.China CIMMYT China Office/CAAS Beijing 100081 P.R.China Beijing Engineering and Technique Research Center of Hybrid Wheat Beijing Academy of Agricultural and Forestry Sciences Beijing 100097 P.R. China

ζ （zeta）-carotene desaturase （ZDS） is a key enzyme for carotenoid biosynthesis, demonstrating high association with the yellow pigment （YP） content in wheat grain. Cloning ZDS gene and developing functional markers are important for marker-assisted selection in wheat breeding. In the present study, the full-length DNA sequence of a ZDS gene on wheat chromosome 2A, designated TaZds-A1, was cloned, with 14 exons and 13 introns, and it has an open reading frame （ORF） of 1 707 bp, encoding 568 amino acid residues. A co-dominant functional marker, YP2A-1, was designed based on the polymorphisms of two alleles at the locus, TaZds-Ala and TaZds-Alb, yielding 183- and 179-bp fragments in TaZds-Ala and TaZds-Alb genotypes, respectively. A new QTL for YP content was detected on chromosome 2A, co-segregating with the functional marker YP2A-1 and TaZds-A1; it explained 11.3% of the phenotypic variance for YP content in a doubled haploid （DH） population from Zhongyou 9507/CA9632. Among 217 Chinese wheat cultivars and advanced lines, the average grain YP content of 126 cultivars with TaZds-Alb allele was 7.8% higher than that of 91 cultivars with TaZds- Ala allele.

关键词： Triticum aestivum functional marker QTL ζ-carotene desaturase ZDS

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In situ Injectable Tetra-PEG Hydrogel Bioadhesive for Sutureless Repair of Gastrointestinal Perforation

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Chinese Journal of Chemistry 2023年第23期41卷 3339-3348页

作者： Shurong Li Yiwen xian Gang he Luyuan Chen Zhihui Chen Yonglong Hong Chong zhang Decheng Wu Guangdong Provincial Key Laboratory of Advanced Biomaterials Department of Biomedical EngineeringSouthern University of Science and TechnologyNo.1088 Xueyuan AvenueNanshan DistrictShenzhenGuangdong518055 China These authors contribute equally. Stomatology Center Shenzhen HospitalSouthern Medical UniversityNo.1333 New RoadBaoan DistrictShenzhenGuangdong518101 China

Hydrogel bioadhesives represent promising and efficient alternatives to sutures or staples for gastrointestinal(GI)perforation ***,several concerns remain for the existing bioadhesives including slow and/or weak adhesive,poor mechanical strength,low biocompatibility,and poor biodegradability,which largely limit their clinical application in GI perforation *** this work,we introduce an in situ injectable Tetra-PEG hydrogel bioadhesive(SS)composed of tetra-armed poly(ethylene glycol)amine(Tetra-PEG-NH2)and tetra-armed poly(ethylene glycol)succinimidyl succinate(Tetra-PEG-SS)for the sutureless repair of GI *** SS hydrogel exhibits rapid gelation behavior and high burst pressure and is capable of providing instant robust adhesion and fluid-tight sealing in the ex vivo porcine intestinal and gastric ***,the succinyl ester linkers in the SS hydrogel endow the bioadhesive with suitable in vivo degradability to match the new GI tissue *** in vivo evaluation in the rat GI injured model further demonstrates the successful sutureless sealing and repair of the intestine and stomach by the SS hydrogel with the advantages of neglectable postsurgical adhesion,suppressed inflammation,and enhanced ***,our results support potential clinical applications of the SS bioadhesive for the high-efficient repair of GI perforation.

关键词： Gastrointestinal perforation Bioadhesives Gels Biological activity Sutureless repair Regenerative wound healing

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Multi-channel signal parameters joint optimization for GNSS terminals

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Journal of Systems Engineering and Electronics 2018年第1期29卷 39-47页

作者： WANG Qian zhang Chuanding xian Deyong Beijing Satellite Navigation Center Beijing 100094China

Traditional global navigation satellite system(GNSS)terminals for satellite navigation adopt independent channels to track the signals from different satellites, which results in a lack of information interaction between the channels. Inspired by the vector tracking idea, and drawing lessons from the principle that in the position domain the Taylor expanded pseudorange observations can be used for positioning via the least squares method, this paper proposes a novel least squares-based multi-channel parameter joint estimation(MPJE) method in the signal domain, which not only retains the advantages of channel fusion, but also maintains the flexibility and diversity of the localization algorithm. With achieving optimal carrier to noise ratio as the goal, the proposed method obtains the required code loop and carrier loop parameters for signal tracking in the domain of whole channels. Experimental results indicate that this method fully achieves the assistant fusion advantages of frequency lock loop(FLL), phase lock loop(PLL)and delay lock loop(DLL), making good use of the robustness and dynamic properties of the FLL and the measurement accuracy of the DLL, and is helpful for achieving stable and accurate signal tracking under weak signals and high dynamic stress environments.

关键词： least squares method signal parameter optimization vector tracking global navigation satellite system(GNSS) weight matrix

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[Cs_(6)Cl][Ga_(5)GeQ_(12)](Q=S,Se):two novel porous layered chalcohalides exhibiting two-band emission and ion exchange properties

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Science China Chemistry 2022年第10期65卷 1903-1910页

作者： Ruiqi Wang xian zhang Fuqiang Huang Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China State Key Laboratory of High-Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China

The salt-inclusion materials have drawn significant attention for their manifold structural chemistry and novel physical/chemical ***,two new salt-inclusion chalcohalides,[Cs_(6)Cl][Ga_(5)GeQ_(12)](Q=S,Se),have been discovered via hightemperature flux *** two isostructural compounds are constructed by porous[Ga_(5)GeQ_(12)]^(5−)layers with[ClCs_(6)]^(5+)octahedra filled in the ***[Ga_(5)GeQ_(12)]^(5−)layer is composed of the honeycomb-like(Ga/Ge)_(18)Q_(42)rings containing(Ga/Ge)_(3)Q_(9)trimer as basic *** band gaps of the two compounds are 3.90 and 2.89 eV,respectively.[Cs_(6)Cl][Ga_(5)GeS_(12)]exhibits interesting two-band emission properties which are related to the intermediate-band electronic structure revealed by density functional theory(DFT)*** to the porous layered structure,[Cs_(6)Cl][Ga_(5)GeS_(12)]exhibits topological ion exchange ability towards Cd^(2+)ions with the maximum sorption capacity of 250 mg/g and high distribution coefficient(Kd)near 106 mL/*** work further enriches the structural diversity of salt-inclusion materials and extends their potential application range to ion exchange adsorption.

关键词： heteroanionic compound layered structure two-band emission ion exchange properties

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Freezing the kinase signaling of breast cancer with transformable peptide nanoparticles

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Science China Chemistry 2020年第8期63卷 1021-1022页

作者： Di-Wei Zheng xian-Zheng zhang Key Laboratory of Biomedical Polymers of Ministry of Education&Department of Chemistry Wuhan UniversityWuhan 430072China

Protein kinases have been recognized as dominant regulators of all aspects of tumor progression,including tumorigenesis,proliferation,invasion,and metastasis[1].During the activation of protein kinases,the binding of ligands(e.g.,epidermal growth factor,transforming growth factor-α,and amphiregulin)can cause dimerization,which promotes the cell growth and triggers a cascade of downstream signaling pathways.

关键词： invasion metastasis breast

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Visible and Near-Infrared Diffuse Reflectance Spectroscopy for Prediction of Soil Properties near a Copper Smelter

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Pedosphere 2012年第3期22卷 351-366页

作者： XIE xian-Li PAN xian-zhang SUN Bo Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China)

Spatial and temporal monitoring of soil properties in smelting regions requires collection of a large number of sam- ples followed by laboratory cumbersome and time-consuming measurements. Visible and near-infrared diffuse reflectance spectroscopy （VNIR-DRS） provides a rapid and inexpensive tool to predict various soil properties simultaneously. This study evaluated the suitability of VNIR-DRS for predicting soil properties, including organic matter （OM）, pH, and heavy metals （Cu, Pb, Zn, Cd, and Fe）, using a total of 254 samples collected in soil profiles near a large copper smelter in China. Partial least square regression （PLSR） with cross-validation was used to relate soil property data to the reflectance spectral data by applying different preprocessing strategies. The performance of VNIR-DRS calibration models was evaluated using the coefficient of determination in cross-validation （R^2cv） and the ratio of standard deviation to the root mean standard error of cross-validation （SD/RMSEcv）. The models provided fairly accurate predictions for OM and Fe （R2v 〉 0.80, SD/RMSEcv 〉 2.00）, less accurate but acceptable for screening purposes for pH, Cu, Pb, and Cd （0.50 〈 Rcv 〈 0.80, 1.40 〈 SD/RMSEcv 〈 2.00）, and poor accuracy for Zn （R2v 〈 0.50, SD/RMSEcv 〈 1.40）. Because soil properties in conta- minated areas generally show large variation, a comparative large number of calibrating samples, which are variable enough and uniformly distributed, are necessary to create more accurate and robust VNIR-DRS calibration models. This study indicated that VNIR-DRS technique combined with continuously enriched soil spectral library could be a nondestructive alternative for soil environment monitoring.

关键词： heavy metal organic matter partial least squares regression soil environment monitoring spectral preprocessing

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Observation of Photoassociation Spectra of Ultracold ^(174)Yb Atoms at ^(1)S_(0)-^(3)P_(1) Inter-Combination Line

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Chinese Physics Letters 2013年第7期30卷 68-71页

作者： LONG Yun XIONG Zhuan-xian zhang Xi zhang Meng-Jiao LÜBao-Long he Ling-xiang Key Laboratory of Atomic Frequency Standards(KLAFS) Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071 University of Chinese Academy of Sciences Beijing 100049

Photoassociation(PA)of cold atoms is a key tool widely used for accurate determination of long-range molecular potentials,measurement and tuning of interatomic interactions,as well as creation of desired cold *** report the observation of PA spectra of ultracold ytterbium(Yb)atoms at the ^(1)S_(0)–^(3)P_(1) inter-combination line by detecting the resonant loss of atoms trapped in a crossed far-off-resonance trap(crossed-FORT).Eight vibrational levels in the ^(1)0^(+)_(u) molecular state are observed for PA laser detunings up to 1 GHz with respect to the atomic *** photoassociation resonances have a Lorentzian shape and sub-MHz linewidths due to the ultra low temperature of the atoms,and the resonance positions agree well with that predicted by the semiclassical formula.

关键词： formula. resonant vibrational

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Characteristics of secondary droplets produced by the impact of drops onto a smooth surface

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Advances in Aerodynamics 2021年第1期3卷 623-634页

作者： Haixiang zhang Ye Gao Xiwen zhang xian Yi Yanxia Du Feng he Zheyan Jin Pengfei Hao Applied Mechanics Laboratory Department of Engineering MechanicsTsinghua University100084 BeijingChina Key Laboratory of Icing and Anti/De-Icing of Aerocraft China Aerodynamics Research and Development CenterSichuan 621000 MianyangChina School of Aerospace Engineering and Applied Mechanics Tongji University200092 ShanghaiChina.

This work investigates the splashing behaviors of droplets impacting on solid surfaces and mainly focuses on the characteristics of secondary *** to the experimental results,two different splashing patterns,corona splash and levitating-lamella breakup,are observed.A new breakup mode,named rimsegmenting,is found during the levitating-lamella *** particular,the detailed information of the splashing secondary droplets,including the size,velocity,angle,and total volume of the splashing secondary droplets is obtained from the experimental *** size distribution of the splashing secondary droplets obeys the gamma distribution *** average diameter and splashing angle of the secondary droplets are mainly related to the Reynolds number Re,and can be expressed as functions of *** impact velocity and liquid viscosity will result in a wider size distribution range of splashing secondary *** also put forward an empirical model to predict the total splashing volume,which is consistent with the experimental data both in this work and previous *** work is believed to provide insights on the prediction of the characteristics of splashing secondary droplets.

关键词： Splashing Droplet Impact Secondary droplets

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Highly Cis-1,4 Selective Polymerization of Conjugated Dienes Catalyzed by ^-heterocyclic Carbene-ligated Neodymium Complexes

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Chinese Journal of Polymer Science 2020年第12期38卷 1305-1312页

作者： Shu zhang Na Wu Yi-xian Wu State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Neodymium complexes containing N heterocyclic carbene(NHC)ligands,NdCl5[1,3,R(NCH=)2C]-THF,(Nd1:R=2,6-Pr2C6H3,x=0;Nd2:R=2,6-Et2C6H3,x=1;Nd3:R=2.4,6-Me3C6H2,x=1)were synthesized and employed as precatalysts for the coordination polymerization of conjugated dienes(butadiene and isoprene).In combination with trisobutylaluminium(TIBA),Nd1 promoted butadiene polymerization to produce extremely high cis-1,4(up to 99.0%)polybutadienes with high molecular weight(Mw=250-780 kg·mol 1).The Nd1/TIBA catalytic system also exhibited both high catalytic activity and cis-1,4 selectivity(up to 97.8%)for isoprene *** catalytic activity,molecular weight and molecular weight distribution of resulting polydienes were directly influenced by Al/Nd molar ratio,aging method,and polymerization *** interestingly,the high cis-1,4 selectivity of the catalyst towards butadiene and isoprene kept almost unchanged under different reaction *** cis-1,4 polyisoprenes with high molecular weight(Mw=210-530 kg·mol 1)and narrow molecular weight distribution (Mw/Mn=1.9-2.7)as well as high cis-1.4 selectivity(-~97%)could be synthesized by using the aged Nd1/TIBA catalytic system in the presence of isoprene(100 equivalent to Nd)at low AlNd molar ratios of *** with low molecular weights(Mw=12-76 kg·mol-7)and narrow molecular weight distributions (Mw/Mn=1.7-2.6)were obtained by using Nd2 and Nd3 as precatalysts,indicating that the molecular weight of resulting polyisoprenes can be adjusted by changing the substitutes of ligand in Nd complex.

关键词： Neodymium complex N heterocydic carbene igand Coordination polymerization Cis-14 sletivity Aging method

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