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Cotton cultivation technology with Chinese characteristics has driven the 70-year development of cotton production in China

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Journal of Integrative Agriculture 2022年第3期21卷 597-609页

作者： FENG Lu CHI Bao-jie DONG He-zhong Zhengzhou Research Base State Key Laboratory of Cotton Biology School of Agricultural Sciences Zhengzhou University Cotton Research Center Shandong Academy of Agricultural Sciences College of Agricultural Science and Technology Shandong Agriculture and Engineering University

Since the founding of the People’s Republic of China in 1949,significant achievements have been made in cotton production in *** has maintained its position as the world’s largest cotton producer for 33 years(1983–2015),with average annual increases of 3.5 and 3.9% in the unit yield and total output of cotton,*** production has played an extremely important role in the development of the national economy and the improvement of living *** the cotton planting area has been reduced in recent years,the total output has remained relatively unchanged due to the continuous increase in the unit ***’s dominant position in global cotton production is undoubtedly attributed to the progress and development of cotton cultivation *** the past 70 years,China has established a high-yielding and high-efficiency cotton cultivation mode that corresponds to its national conditions,including a large population and a limited land ***,cotton cultivation technology is constantly being innovated and developed to keep pace with the *** this paper,we review the development of cotton production and cultivation in China over the past 70 years,with a particular focus on the innovation and development of cotton cultivation technology with Chinese *** review is intended to provide guidance for the sustainable development of China’s cotton production in the future and to provide a reference for global cotton production.

关键词： China cotton cultivation technology outlook

Enhancement of red emission assigned to inversion defects in ZnAl2O4:Cr3+ hollow spheres

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Frontiers of Materials Science 2020年第1期14卷 73-80页

作者： Dong Zhang Jingxin Chen Chunyu Du Bingjun Zhu Qingru Wang Qiang Shi Shouxin Cui Wenjun Wang School of Physical Science and Information Technology Shandong Key Laboratory of Optical Communication Science and TechnologyLiaocheng UniversityLiaocheng252059China

ZnAl2O4:Cr3+hollow spheres composed of secondary nanoparticles with single spinel phase were fabricated using carbon *** the emission of 687 nm,two wide excitation bands attributed to the electrons of Cr3+transiting from 4A2g(4F)→4T1g(4F)and 4A2g(4F)→4T2g(4F)were *** broad excitation band at about 397 nm was asymmetric and consisted of two peaks,indicating that there was a trigonal distortion existing in the *** intensity of all emitting peaks revealed sharp increasing trend with the sintering temperature increase,and the intensity of emission at 698 nm assigned to inversion defects was more intense than that of emission at 687 nm assigned to octahedral Cr3+ions in the undistorted spinel *** samples with higher synthesized temperature revealed longer decay time,and the relative weightage of shorter decay time component decreased with the increase of sintering temperature,indicating that the surface defects decreased.

关键词： semiconductors hollow sphere inversion defects photoluminescence

Novel Intermolecular C-H…π Interactions from a One-dimensional Chain:Synthesis and Crystal Structure of a Ladder Dibenzyl Tin Carboxylate

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Chinese Journal of Structural Chemistry 2010年第2期29卷 285-289页

作者：康万利吴瑞坤孟令伟吴晓燕 EOR Research Center China University of Petroleum

The title ladder organotin carboxylate,{[（C6H5CH2）2Sn]4（p-NH2C6H4-COO）2O2（OCH3）2}·0.5H2O 1,has been synthesized and structurally characterized by elemental analyses,IR and single-crystal X-ray diffraction *** 1 is located across on an inversion center and displays a Sn4O4 ladder-like structure with a one-dimensional supramolecular chain through C-H…π *** the asymmetric unit two Sn（Ⅳ） atoms assume similar trigonal bipyramidal coordination *** aminobenzoate groups coordinate to the terminal Sn（Ⅳ） *** deprotonated methanol molecule bridges two independent Sn（Ⅳ） atoms.A half of lattice water molecule is disorderly filled in the cavity formed by Sn（Ⅳ） complexes.

关键词： organotin(Ⅳ) carboxylate 4-aminobezoic acid dibenzyldichlorostannane crystal structure

Mine pressure regularity of working across over roadway and control effect analysis

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Journal of Coal Science & Engineering(China) 2007年第4期13卷 420-424页

作者：李伟王玉和程久龙 Key Laboratory of Mine Disaster Prevention and Control Shandong University of Science ＆ Technology Qingdao 266510 China Xiezhuang Colliery Xinwen Mining Industry Group Xintai 271200 China

Analyzed roof rock layer structure and rock layer thickness of -550 level west main roadway and proposed that the stability of calcareous rock layer was the premise of mining successfully. According to different roof condition and rock pillar size of main roadway, different reinforcement plans were used to strengthen the stability of rock layer. By studying the influence rule and influence scope of dynamic pressure of main roadway wall rock because of fully mechanized coal face extracting, that the size of rock pillar was the key of affecting wall rock distorting was proposed. Scientific basis was provided for determining the size of reasonable rock pillar, selecting reasonable extracting support plan and reinforcement measures under different wall rock conditions.

关键词： mine pressure regularity working across over roadway control effect

construction of Self-Assembly Based Tunable Absorber:Lightweight,Hydrophobic and Self-Cleaning Properties

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Nano-Micro Letters 2023年第9期15卷 148-163页

作者： Zehua Zhou Qianqian Zhu Yue Liu Yan Zhang Zirui Jia Guanglei Wu Institute of Materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071People’s Republic of China

Although multifunctional aerogels are expected to be used in applications such as portable electronic devices,it is still a great challenge to confer multifunctionality to aerogels while maintaining their inherent ***,a simple method is proposed to prepare multifunctional NiCo/C aerogels with excellent electromagnetic wave absorption properties,superhydrophobicity,and self-cleaning by water-induced NiCo-MOF ***,the impedance matching of the three-dimensional(3D)structure and the interfacial polarization provided by CoNi/C as well as the defect-induced dipole polarization are the primary contributors to the broadband *** a result,the prepared NiCo/C aerogels have a broadband width of 6.22 GHz at 1.9 *** to the presence of hydrophobic functional groups,CoNi/C aerogels improve the stability in humid environments and obtain hydrophobicity with large contact angles>140°.This multifunctional aerogel has promising applications in electromagnetic wave absorption,resistance to water or humid environments.

关键词： MOF aerogel Self-cleaning Electromagnetic wave absorption Hydrophobic

Research progress of optoelectronic devices based on two-dimensional MoS_(2) materials

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Rare Metals 2023年第1期42卷 17-38页

作者： Liang-Rui Zou Dan-Dan Sang Yu Yao Xue-Ting Wang Yuan-Yuan Zheng Nai-Zhou Wang Cong Wang Qing-Lin Wang shandong Key Laboratory of Optical Communication Science and Technology School of Physics Science and Information TechnologyLiaocheng UniversityLiaocheng252000China College of Mathematics and Physics Beijing University of Chemical TechnologyBeijing100029China Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore637371Singapore

Molybdenum disulfide(MoS_(2))is a widely used optoelectronic material with exceptional electrical,magnetic,optical,and mechanical *** to the quantum confinement effect,high absorption coefficient,high surface-volume ratio,and tunable bandgap,nanoMoS_(2)-based devices exhibit size-dependent and novel optoelectronic properties,such as excellent photoluminescence and high anisotropic electrical,mechanical,and thermal *** review focuses mainly on the latest progress of optoelectronic device applications based on two-dimensional(2D)nano-MoS_(2).Various advanced devices,such as sensors,photodetectors,light-emitting diodes(LEDs),memory applications,and field-effect transistors(FETs)are *** review will provide a new perspective in promoting the development of 2D nanomaterial-based photoelectric applications.

关键词： MoS_(2) Optoelectronics Devices Nano Materials

Research on application of transient electromagnetic technology in coal mine

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Journal of Coal Science & Engineering(China) 2007年第3期13卷 310-313页

作者：王玉和李伟程久龙 Key Laboratory of Mine Disaster Prevention and Control Shandong University of Science ＆ Technology Qingdao 266510 China Xiezhuang Colliery Xinwen Mining Industry Group Xintai 271200 China

Studied the principle of transient electromagnetic method in coalmine and solved the computation of the whole time apparent resistivity and the relation between apparent resistivity and exploration depth and so on. Studied the work method of transient electromagnetic method in coalmine and obtained reasonable arrangement way. Studied data processing and explanation method of transient electromagnetic method and obtained high quality electric section. Finally the purpose to detect water-bearing body and water-bearing structure in front of roadway in advance, and detect the water-bearing property of the roof and floor rock layer of coal face were realized by use of transient electromagnetic method.

关键词： mine transient electromagnetic method whole time apparent resistivity roadway advanced detection the roof and floor of coalface water-bearing property detection

An in Vitro Investigation of Acid Etching Treatment Prior to Post and Core Cementation and Teeth Fracture Resistance

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Journal of Wuhan University of Technology(Materials Science) 2019年第5期34卷 1233-1237页

作者： MA Xiaoni GAO Xu XU Xin School of Stomatology Shandong UniversityJinan 250012China Handong Provincial Key Laboratory of Oral Tissue Regeneration Jinan 250012China School of Material Science and Engineering Shandong UniversityJinan 250012China Yantai Stomatological Hospital Yantai 264000China

In order to investigate how to enhance the teeth fracture resistance after the post and core treatment, an in vitro study was conducted to measure the fracture resistance of endodontically treated teeth restored with cast post and core with two kinds of surface treatment technology and acid etching preparation on the dentinal surface. Sixty-four recently extracted human single-rooted first premolars were endodontically treated and sectioned approximately 1.5 mm above the cementoenamel junction to remove the coronal portion. Each specimen received a cast post, core build-up and a metal alloy crown restoration. All teeth were randomly divided into the smooth surface post, core repair group, the sand blasting surface post, and core repair group, each group was divided into 10 s, 30 s, 60 s acid corrosion treatment group and control group. In acid test groups, an acid etching solution was applied for 10, 30 and 60 seconds, respectively, to the root canal wall surface. Each specimen was embedded in acrylic resin block and tested in an electronic universal testing machine. Fracture loads results showed that canal acid etching could increase teeth fracture resistance strength both in smooth groups and sandblasting group, and achieved the best effect when acid etching for 30 s. Sand spray treatment on the surface of the cast metal post can improve the flexural strength of the teeth after postcrown restoration. Acid etching on the root canal wall surfaces and sand spray treatment on the surface of the cast metal post can improve the flexural strength of the root after post-crown restoration. Therefore, these two methods could be used to strengthen the tooth fracture resistance, and maintain the long-term therapeutic effect of cast post and core restoration.

关键词： acid etching cast post and core resistance strength surface treatment

Macroscopic electromagnetic synergy network-enhanced N-doped Ni/C gigahertz microwave absorber with regulable microtopography

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Nano Research 2023年第7期16卷 10666-10677页

作者： Yuelei Pan Qianqian Zhu Jiahui Zhu Yuhang Cheng Bowen Yu Zirui Jia Guanglei Wu Institute of Materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071China

To achieve excellent electromagnetic wave(EMW)absorption properties,the microstructure design of the absorber is *** this work,six kinds of N-Ni/C nanostructures with different morphologies were prepared by one-step hydrothermal method and high temperature carbonization by adjusting the types of nickel salts and reaction *** EMW absorption performance of six different morphologies of N-Ni/C nanostructures was compared and *** them,it is found that the nanoflowerlike N-Ni/C composite has excellent dielectric loss and magnetic loss synergistic effect due to its polycrystalline structure,and can obtain excellent EMW absorption *** minimum reflection loss value at a thickness of 1.9 mm is-59.56 dB at 16.88 GHz,and the effective absorption bandwidth value reaches 6.0 GHz at a thickness of 2.2 *** research shows that different morphologies and multiple lattice structures of nanostructures with the same composition have a significant influence on EMW absorption performance,which provides new research ideas for developing high-performance EMW absorbing materials.

关键词： magnetic metal-carbon binary composition morphology control dielectric loss magnetic loss electromagnetic wave absorption