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Impact of Different Rates of Nitrogen Supplementation on Soil PhysicochemicalProperties and Microbial Diversity in Goji Berry
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作者 Xiaojie Liang Wei An +4 位作者 Yuekun Li Yajun Wang Xiaoya Qin Yanhong Cui Shuchai Su 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期467-486,共20页
Goji berry(Lycium barbarum L.)is substantially dependent on nitrogen fertilizer application,which can signifi-cantly enhance fruit yield and Goji berry industrial development in Ningxia,China.This study aimed to analyz... Goji berry(Lycium barbarum L.)is substantially dependent on nitrogen fertilizer application,which can signifi-cantly enhance fruit yield and Goji berry industrial development in Ningxia,China.This study aimed to analyze the functions of differential nitrogen application rates including low(N1),medium(N2),and high(N3)levels in soil microbial community structure(bacterial and fungal)at 2 diverse soil depths(0-20,20-40 cm)through high-throughput sequencing technology by targeting 16S RNA gene and ITS1&ITS2 regions.All the observed physicochemical parameters exhibited significant improvement(p<0.05)with increased levels of nitrogen and the highest values for most parameters were observed at N2.However,pH decreased(p<0.05)gradually.The alpha and beta diversity analyses for bacterial and fungal communities’metagenome displayed more similarities than differences among all groups.The top bacterial and fungal phyla and genera suggested no obvious(p>0.05)differences among three group treatments(N1,N2,and N3).Furthermore,the functional enrichment analysis demonstrated significant(p<0.05)enrichment of quorum sensing,cysteine and methionine metabolism,and transcriptional machinery for bacterial communities,while various saprotrophic functional roles for fungal communities.Conclusively,moderately reducing the use of N-supplemented fertilizers is conducive to increasing soil nitrogen utilization rate,which can contribute to sustainable agriculture practices through improved soil quality,and microbial community structure and functions. 展开更多
关键词 Goji berry production Ningxia China differential nitrogen supplementation rates 16s RNA gene and IT1&IT2 region sequencing soil physicochemical properties
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Petrophysical properties and their influencing factors of carbonates in the fourth member of Sinian Dengying Formation, Sichuan Basin, SW China
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作者 WANG Jiaqing DENG Jixin +2 位作者 LIU Zhonghua YAN Longlong XIA Hui 《Petroleum Exploration and Development》 SCIE 2023年第6期1358-1373,共16页
Based on the measurements of petrological, petrophysical and elastic properties of the samples of different sedimentary facies in the fourth member of Sinian Dengying Formation (Deng 4 Member) in the Sichuan Basin, th... Based on the measurements of petrological, petrophysical and elastic properties of the samples of different sedimentary facies in the fourth member of Sinian Dengying Formation (Deng 4 Member) in the Sichuan Basin, the diagenetic processes of reservoirs of different sedimentary facies and their controls on the petrophysical properties were discussed. The results show that cracks and mineral composition jointly control the petrophysical properties, and both are significantly influenced by sedimentary environment and diagenesis. The microbial dolomite of mound-shoal facies mainly experienced multi-stage dolomitization, penecontemporaneous dissolution, tectonic rupture and hydrothermal/organic acid dissolution processes, giving rise to cracks and dissolved pores. The grannular dolomite of inter-mound-shoal bottomland or dolomitic lagoon facies mainly underwent mechanical compaction, burial dolomitization and tectonic-hydrothermal action, creating cracks and intercrystalline pores. The diagenesis related to crack development increases the pressure- and saturation-dependent effects of samples, leading to significant decrease in the compressional wave impedance and Poisson's ratio. Dolomitization changes the properties of mineral particles, resulting in a Poisson's ratio close to dolomite. The muddy, siliceous and calcareous sediments in the low-energy environment lead to the decrease of impedance and the differential change of Poisson's ratio (significantly increased or decreased). The samples with both cracks and dissolved pores show high P-wave velocity dispersion characteristics, and the P-wave velocity dispersion of samples with only fractures or pores is the lowest. 展开更多
关键词 sichuan Basin sinian Dengying Formation carbonate rock sedimentary environment DIAGENEsIs petrophysical properties wave impedance Poisson’s ratio P-wave velocity dispersion
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双金属MOFs碳化材料的结构对锂硫电池正极性能的影响 被引量:1
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作者 曹翔宇 张秀玲 +2 位作者 杜依洋 马成乡 闫娟枝 《化工新型材料》 CAS CSCD 北大核心 2024年第1期150-155,160,共7页
利用硝酸钴和铁氰化钾在水溶液中沉淀反应以及ZIF-8在水溶液中的部分分解,分别制备了2种组成相近但结构不同的双金属有机框架前驱体Co-Fe precursor和ZCF precursor。经过多巴胺包覆,对2种产品在氩气气氛下退火获得碳化产物。将碳化产... 利用硝酸钴和铁氰化钾在水溶液中沉淀反应以及ZIF-8在水溶液中的部分分解,分别制备了2种组成相近但结构不同的双金属有机框架前驱体Co-Fe precursor和ZCF precursor。经过多巴胺包覆,对2种产品在氩气气氛下退火获得碳化产物。将碳化产物与纳米硫粉混合得到的碳/硫复合材料(E-CoFeCN@C/S、E-ZCF@C/S)分别作为正极,组装扣式锂硫电池并测试电化学性能。利用X射线衍射仪、扫描电子显微镜、透射电子显微镜、热重分析仪进行形貌和结构分析。在组成相似的情况下,核壳结构碳载体(E-CoFeCN@C)与发散式结构碳载体(E-ZCF@C)对锂硫电池性能的影响呈现出“此消彼长”的特点:E-ZCF@C/S在循环伏安测试中表现出更小的极化以及更强的电流响应,在电化学阻抗测试中表现出更低的电荷转移阻抗,表明该材料有利于促进正极电荷传递过程,即加快电极反应动力学。E-ZCF@C/S在0.2C倍率下放电初始比容量为1211.3mAh/g,在2C倍率下放电初始比容量为794mAh/g,均优于E-CoFeCN@C/S。而核壳结构的优势主要体现在容量衰减方面,E-CoFeCN@C/S在0.2C倍率下经过100次循环后平均衰减率为0.074%(E-ZCF@C/S为0.26%),在2C倍率下循环300次后平均衰减率为0.047%(E-ZCF@C/S为0.13%),说明核壳结构对活性物质的锚固作用明显而对电荷转移不利。 展开更多
关键词 双金属MOFs 锂硫电池 材料结构 电化学性能
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Chemical bonding and elastic properties of quaternary arsenide oxides YZnAsO and LaZnAsO investigated by first principles
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作者 施毅敏 叶绍龙 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第6期1378-1382,共5页
The structural parameters, chemical bonding and elastic properties of the tetragonal phase quaternary arsenide oxides YZnAsO and LaZnAsO were investigated by using density-functional theory (DFT) within generalized ... The structural parameters, chemical bonding and elastic properties of the tetragonal phase quaternary arsenide oxides YZnAsO and LaZnAsO were investigated by using density-functional theory (DFT) within generalized gradient approximation (GGA). The GGA calculated structural parameters are in agreement with the experimental results. Population analysis suggests that the chemical bonding in YZnAsO and LaZnAsO can be classified as a mixture of ionic and covalent characteristic. Single-crystal elastic constants were calculated and the polycrystalline elastic modules were estimated according to Voigt, Reuss and Hill's approximations (VRH). The result shows that both YZnAsO and LaZnAsO are relatively soft materials exhibiting ductile behavior. The calculated polycrystalline elastic anisotropy result shows that LaZnAsO is more anisotropy in compressibility and YZnAsO is more anisotropy in shear. 展开更多
关键词 YZnAsO LaZnAsO chemical bonding elastic properties density-functional theory generalized gradientapproximation Voigt Reuss and Hill's approximations
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Fabrication and photocatalytic properties of Cu_2S/T-ZnO_w heterostructures via simple polyol process 被引量:1
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作者 吴德智 范希梅 +2 位作者 田轲 代佳 刘花蓉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第7期1620-1628,共9页
The Cu2S/tetrapod-like ZnO whisker(T-ZnOw) heterostructures were successfully synthesized via a simple polyol process employing the poly(vinyl pyrrolidone)(PVP) as a surfactant.The as-prepared heterostructures w... The Cu2S/tetrapod-like ZnO whisker(T-ZnOw) heterostructures were successfully synthesized via a simple polyol process employing the poly(vinyl pyrrolidone)(PVP) as a surfactant.The as-prepared heterostructures were characterized by X-ray diffraction(XRD),field emission scanning electron microscopy(FESEM),X-ray photoelectron spectroscopy(XPS) and Fourier transform infrared(FTIR).The photocatalytic properties of Cu2S/T-ZnOw nanocomposites synthesized with different PVP concentrations were evaluated by photodegradation of methyl orange(MO) under UV irradiation.The results show that the Cu2S/T-ZnOw nanocomposites exhibit remarkable improved photocatalytic property compared with the pure T-ZnOw.The sample prepared with 3.0 g/L PVP shows an excellent photocatalytic property and the highest photodegradation rate of MO is 97% after UV irradiation for 120 min.Besides,the photocatalytic activity of the photocatalyst has no evident decrease even after four cycles,which demonstrates that the Cu2S/T-ZnOw photocatalyst exhibits an excellent photostability.Moreover,the photocatalytic mechanism of the Cu2S/T-ZnOw nanocomposites was also discussed. 展开更多
关键词 Cu2s/T-ZnOw heterostructure photocatalytic property Cu2s nanoparticle
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Effects of Zn content on the microstructure and the mechanical and corrosion properties of as-cast low-alloyed Mg–Zn–Ca alloys 被引量:16
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作者 Hong-xiang Li Shi-kai Qin +3 位作者 Hng-zhong Ma Jian WanE Yun-jin Liu Ji-shan Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2018年第7期800-809,共10页
The effects of Zn content on the microstxucture and the mechanical and corrosion properties of as-cast low-alloyed Mg-xZn~.2Ca alloys (x = 0.6wt%, 2.0wt%, 2.5wt%, hereafter denoted as 0.6Zn, 2.0Zn, and 2.5Zn alloys, ... The effects of Zn content on the microstxucture and the mechanical and corrosion properties of as-cast low-alloyed Mg-xZn~.2Ca alloys (x = 0.6wt%, 2.0wt%, 2.5wt%, hereafter denoted as 0.6Zn, 2.0Zn, and 2.5Zn alloys, respectively) axe investigated. The results show that the Zn content not only influences grain refinement but also induces different phase precipitation behaviors. The as-cast microstxucture of the 0.6Zn alloy is composed of ct-Mg, Mg2Ca, and Ca2Mg6Zn3 phases, whereas 2.0Zn and 2.5Zn alloys only contain ct-Mg and Ca2Mg6Zn3 phases, as revealed by X-ray diffraction (XRD) and txonsmission electron microscopy (TEM) analyses. Moreover, with in- creasing Zn content, both the ultimate tensile strength (UTS) and the elongation to fracture first increase and then decrease. Among the three investigated alloys, the largest UTS (178 MPa) and the highest elongation to fracture (6.5%) are obtained for the 2.0Zn alloy. In addition, the corrosion rate increases with increasing Zn content. This paper provides on updated investigation of the alloy composi- tion-microstxucture-property relationships of different Zn-containing Mg-Zn-Ca alloys. 展开更多
关键词 Mg-Zn-Ca alloy s as-cast micro stxucture mechanical properties corrosion properties
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Interactions of Sn and S and their effects on the magnetic properties of non-oriented silicon steel sheets 被引量:8
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作者 ZHANG Feng WANG Bo +1 位作者 LV Xuejun CHEN Lingyun 《Baosteel Technical Research》 CAS 2013年第2期12-16,共5页
The interactions of Sn and S and their effects on the magnetic properties of non-oriented silicon steel sheets were discussed in reference to industrial production. Results show that minor amounts of Sn can improve ma... The interactions of Sn and S and their effects on the magnetic properties of non-oriented silicon steel sheets were discussed in reference to industrial production. Results show that minor amounts of Sn can improve magnetic induction sharply but have little effect on core loss when the S content is below 10 × 10 ^-4%. The precipitation of AlN can be restrained effectively by Sn. Sn, as the nucleus, can remove some of the inclusions with a size of 0.5μm or larger, but has little effect on inclusions smaller than 0.5 μm,which is the key factor affecting core loss. Sn improves the magnetic induction of finished steel sheets mainly through the change of the steel texture. The relationship between the magnetic induction and Sn and S content can be regressed as B50 = 1.69 -4.37 ws +0.30 Ws,. From the regression formulation,the magnetic induction can be improved by 0.03 T when 0.01% Sn is added under relatively low S content conditions. 展开更多
关键词 silicon steel sN s INTERACTION magnetic property
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Effects of reclaimed water irrigation and nitrogen fertilization on the chemical properties and microbial community of soil 被引量:11
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作者 GUO Wei Mathias N Andersen +4 位作者 QI Xue-bin LI Ping LI Zhong-yang FAN Xiang-yang ZHOU Yuan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第3期679-690,共12页
The ecological effect of reclaimed water irrigation and fertilizer application on the soil environment is receiving more attention.Soil microbial activity and nitrogen(N)levels are important indicators of the effect... The ecological effect of reclaimed water irrigation and fertilizer application on the soil environment is receiving more attention.Soil microbial activity and nitrogen(N)levels are important indicators of the effect of reclaimed water irrigation on environment.This study evaluated soil physicochemical properties and microbial community structure in soils irrigated with reclaimed water and receiving varied amounts of N fertilizer.The results indicated that the reclaimed water irrigation increased soil electrical conductivity(EC)and soil water content(SWC).The N treatment has highly significant effect on the ACE,Chao,Shannon(H)and Coverage indices.Based on a 16S ribosomal RNA(16S rRNA)sequence analysis,the Proteobacteria,Gemmatimonadetes and Bacteroidetes were more abundant in soil irrigated with reclaimed water than in soil irrigated with clean water.Stronger clustering of microbial communities using either clean or reclaimed water for irrigation indicated that the type of irrigation water may have a greater influence on the structure of soil microbial community than N fertilizer treatment.Based on a canonical correspondence analysis(CCA)between the species of soil microbes and the chemical properties of the soil,which indicated that nitrate N(NO3-–-N)and total phosphorus(TP)had significant impact on abundance of Verrucomicrobia and Gemmatimonadetes,meanwhile the p H and organic matter(OM)had impact on abundance of Firmicutes and Actinobacteria significantly.It was beneficial to the improvement of soil bacterial activity and fertility under 120 mg kg^-1 N with reclaimed water irrigation. 展开更多
关键词 reclaimed water NITROGEN soil chemical properties 16s rRNA sequence soil microbe community
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The study on the mechanical properties of PU/MF double shell self-healing microcapsules 被引量:5
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作者 Guohao Du Jianfeng Hu +7 位作者 Jianhui Zhou Guangwu Wang Shengli Guan Hailing Liu Man Geng Chuang Lv Yaoqiang Ming Jinqing Qu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第5期1459-1473,共15页
The self-healing microcapsules can be buried in the coating to improve the anticorrosive ability.In this paper,self-healing microcapsules of polyurea(PU)/melamine resin(MF)double shell were prepared by in-situ polymer... The self-healing microcapsules can be buried in the coating to improve the anticorrosive ability.In this paper,self-healing microcapsules of polyurea(PU)/melamine resin(MF)double shell were prepared by in-situ polymerization and interfacial polymerization with isocyanate as the core material.Scanning electron microscope was used to observe the microcapsule morphology.The structures of microcapsules prepared with different chain extenders were characterized by Fourier transform infrared spectroscopy.The micromanipulation system was used to loading–holding,loading–unloading and loading to rupture individual microcapsules,so as to explore the mechanical properties of microcapsules.The Young’s modulus corresponding to microcapsules was calculated by mathematical model fitting.The self-healing properties of microcapsule coating were characterized by optical microscope.The experimental results showed that the microcapsule shell prepared under optimized conditions had a complete morphology and good mechanical properties.The microcapsule was in the elastic deformation stage under small deformation,and the plastic deformation stage under large deformation.The Young’s modulus range of microcapsules was 9.29–14.51 MPa,and the corresponding Young’s modulus could be prepared by adjusting the process.The surface crack of the coating containing microcapsule could heal itself after48 h in a humid environment. 展开更多
关键词 MICROCAPsULEs sELF-HEALING Double-layered Mechanical properties Young’s modulus
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The protective effect of cyclodextrin on the color quality and stability of Cabernet Sauvignon red wine 被引量:1
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作者 Caiyun Liu Lulu Wu +2 位作者 Shuyue Fan Yongsheng Tao Yunkui Li 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期310-323,共14页
The impact of cyclodextrins(CDs)on wine quality and stability remains largely unknown.This study systematically assessed the protective effect of the post-fermentation addition of CDs on color stability of red wine fr... The impact of cyclodextrins(CDs)on wine quality and stability remains largely unknown.This study systematically assessed the protective effect of the post-fermentation addition of CDs on color stability of red wine from the viewpoints of color characteristics,copigmentation and phenolic profiles.The grey relational analysis(GRA)and principal component analysis(PCA)methods were employed to dissect the key effective determinants related to color quality.The addition of CDs induced a significant hyperchromic effect of 8.19-25.40%,a significant bathochromic effect and an enhancement of the color intensity.Furthermore,the evolution of anthocyanin forms and the content of monomeric anthocyanins revealed that β-CD is a superior favorable cofactor during wine aging,but for long-term aging,2-HP-β-CD and 2-HP-γ-CD are more beneficial in promoting the formation of polymerized anthocyanins and color stability.This work provides an important reference for the use of CDs to enhance the color quality and stability of red wines. 展开更多
关键词 cyclodextrins color properties copigmentation Helan Mountain’s East Foothill red wine aging
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A gated recurrent unit model to predict Poisson’s ratio using deep learning 被引量:1
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作者 Fahd Saeed Alakbari Mysara Eissa Mohyaldinn +4 位作者 Mohammed Abdalla Ayoub Ibnelwaleed A.Hussein Ali Samer Muhsan Syahrir Ridha Abdullah Abduljabbar Salih 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期123-135,共13页
Static Poisson’s ratio(vs)is crucial for determining geomechanical properties in petroleum applications,namely sand production.Some models have been used to predict vs;however,the published models were limited to spe... Static Poisson’s ratio(vs)is crucial for determining geomechanical properties in petroleum applications,namely sand production.Some models have been used to predict vs;however,the published models were limited to specific data ranges with an average absolute percentage relative error(AAPRE)of more than 10%.The published gated recurrent unit(GRU)models do not consider trend analysis to show physical behaviors.In this study,we aim to develop a GRU model using trend analysis and three inputs for predicting n s based on a broad range of data,n s(value of 0.1627-0.4492),bulk formation density(RHOB)(0.315-2.994 g/mL),compressional time(DTc)(44.43-186.9 μs/ft),and shear time(DTs)(72.9-341.2μ s/ft).The GRU model was evaluated using different approaches,including statistical error an-alyses.The GRU model showed the proper trends,and the model data ranges were wider than previous ones.The GRU model has the largest correlation coefficient(R)of 0.967 and the lowest AAPRE,average percent relative error(APRE),root mean square error(RMSE),and standard deviation(SD)of 3.228%,1.054%,4.389,and 0.013,respectively,compared to other models.The GRU model has a high accuracy for the different datasets:training,validation,testing,and the whole datasets with R and AAPRE values were 0.981 and 2.601%,0.966 and 3.274%,0.967 and 3.228%,and 0.977 and 2.861%,respectively.The group error analyses of all inputs show that the GRU model has less than 5% AAPRE for all input ranges,which is superior to other models that have different AAPRE values of more than 10% at various ranges of inputs. 展开更多
关键词 static Poisson’s ratio Deep learning Gated recurrent unit(GRU) sand control Trend analysis Geomechanical properties
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Experimental Study of Seepage Properties of Non-Darcy Flow in Granular Coal Gangues 被引量:4
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作者 MIAO Xie-xing LI Shun-cai +1 位作者 HUANG Xian-wu CHEN Zhan-qing 《Journal of China University of Mining and Technology》 EI 2006年第2期105-109,共5页
By using the steady-state seepage method, a patent seepage device together with the MTS815.02 Rock Mechanics Test System is used to test the seepage properties of non-Darcy flow in a granular gangue with five differen... By using the steady-state seepage method, a patent seepage device together with the MTS815.02 Rock Mechanics Test System is used to test the seepage properties of non-Darcy flow in a granular gangue with five different grain sizes during the compaction. The experimental results show that the seepage properties are not only related to the stress or displacement level, but also to the grain size, the pore structure of the granular gangue, and the current porosity The permeability and the non-Darcy flow coefficient can be fitted respectively by the cubic polynomials and the power functions of the porosity, Formally, the flow in granular gangue satisfies the Forchheimer's binomial flow, but under the great axial and confining pressure and owing to the grain's crushing, the flow in granular gangues is different from that in rock-fills which are naturallv oiled un. As a result, the non-Darer flow coefficient may be negative. 展开更多
关键词 granular coal gangue COMPACTION seepage properties Forchhelmer s binomial flow non-Darcy flow coefficient
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Synthesis and blue light-emitting properties of 4,4'-bis(diphenylamino)-quinque(p-phenyl)s 被引量:1
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作者 Zhong Hui Li Mo Jun Xiong Man Shing Wong 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第7期823-826,共4页
An excellent organic blue light-emitting diode based on 4,4'-bis(diphenylamino)-quinque(p-phenylene)s (OPP(5)-NPh) with a maximum luminance of up to 5000 cd/m^2 and a luminanous efficiency of 1.3 cd/A was rep... An excellent organic blue light-emitting diode based on 4,4'-bis(diphenylamino)-quinque(p-phenylene)s (OPP(5)-NPh) with a maximum luminance of up to 5000 cd/m^2 and a luminanous efficiency of 1.3 cd/A was reported. This diode was made by using a wide band-gap hole-blocking layer, F-TBB instead of PBD in the OLED devices. We attribute the good performance to the one trade-off involved in the use of F-TBB to obtain higher luminance is the increased turn-on voltages and slightly decreased device efficiencies. 展开更多
关键词 4 4'-Bis(diphenylamino)-quinque(p-phenylene)s sYNTHEsIs Organic light-emitting diode (OLED) Optical properties
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进口再生塑料颗粒中双酚A、双酚S的溶出特性研究
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作者 王涛 高红 +3 位作者 岳波 孟棒棒 张颖 刘博 《科技通报》 2024年第4期104-108,113,共6页
为了加强我国进口塑料颗粒的监管,降低我国进口再生塑料颗粒使用风险,建立更加完善、更加严格的限值标准。本文以聚对苯二甲酸乙二醇酯(PET)、聚丙烯(PP)、聚乙烯(PE)、聚苯乙烯(PS)以及丙烯腈-丁二烯-苯乙烯共聚物(ABS)为原料的进口再... 为了加强我国进口塑料颗粒的监管,降低我国进口再生塑料颗粒使用风险,建立更加完善、更加严格的限值标准。本文以聚对苯二甲酸乙二醇酯(PET)、聚丙烯(PP)、聚乙烯(PE)、聚苯乙烯(PS)以及丙烯腈-丁二烯-苯乙烯共聚物(ABS)为原料的进口再生塑料颗粒为研究对象,采用高效液相色谱-紫外检测法对5种进口再生塑料颗粒中双酚A和双酚S的含量进行分析,并进一步探究接触时间、温度及模拟溶液对再生塑料颗粒中双酚A和双酚S溶出的影响。结果表明:(1)5种进口再生塑料颗粒中,ABS颗粒中双酚A、双酚S含量均为最高,含量平均值分别为(69.44±5.32)mg/kg与(125.59±5.62)mg/kg。(2)探究接触时间影响因素过程中,双酚A和双酚S在模拟溶液的溶出量总体在96~168 h内增长较快,直到240 h溶出量达到平衡。(3)探究温度影响因素过程中,在70℃条件下双酚A和双酚S总溶出量均明显大于40℃与25℃。(4)探究模拟溶液影响因素过程中,双酚S在乙酸模拟液中均未溶出,双酚A在乙醇中的溶出量明显高于乙酸,存在相似相溶解效应。 展开更多
关键词 进口再生塑料颗粒 高效液相色谱 双酚A 双酚s 溶出特性
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Artificial network prediction on degradable properties of coal-filled films 被引量:2
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作者 杨志远 周安宁 曲建林 《Journal of Coal Science & Engineering(China)》 2005年第2期78-81,共4页
Utilized degradable data of coal-filled films from the accelerated UV chamber ageing degradation experiments, and on the basis of control factors’ analysis, presented a predicting model on degradable properties of th... Utilized degradable data of coal-filled films from the accelerated UV chamber ageing degradation experiments, and on the basis of control factors’ analysis, presented a predicting model on degradable properties of this film in photo-degradation according to back-propagation artificial neural network (BP ANN). 4 controlling factors in films degrada-tion, including temperature, the time of UV irradiation, the concentration and the type of coals were used as input parameters in the ANN model. While the degradable properties after film degradation, including the mechanical properties and carbonyl index, were used as output parameters. It was carried out by the neural network toolbox of Matlab 6.5 soft-ware and Visual Basic 6.0. Discussed partition of sample data and model’s parameters, and then selected the best configuration of ANN network. The accurate scope of predicting results was analyzed. This model has a high precision in predicting on properties of the coal-filled film degradation. 展开更多
关键词 coal-filled film degradable properties model's parameters ANN PREDICTION
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Bandgap engineering to tune the optical properties of Be_xMg_(1-x)X(X=S, Se, Te) alloys 被引量:1
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作者 B Sabir N A Noor +3 位作者 M Rashid Fasih Ud Din Shahid M Ramay Asif Mahmood 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第1期415-423,共9页
Structural, electronic, and optical properties of alloys BexMgl-xX (X = S, Se, Te) in the assortment 0 〈 x 〈 1 were theoretically reported for the first time in zinc-blende (ZB) phase. The calculations were carr... Structural, electronic, and optical properties of alloys BexMgl-xX (X = S, Se, Te) in the assortment 0 〈 x 〈 1 were theoretically reported for the first time in zinc-blende (ZB) phase. The calculations were carried out by using full-potential linearized augmented plane wave plus local orbitals (FP-LAPW+lo) formalism contained by the framework of density functional theory (DFT). Wu--Cohen (WC) generalized gradient approximation (GGA), based on optimization energy, has been applied to calculate these theoretical results. In addition, we used Becke and Johnson (mBJ-GGA) potential, modified form of GGA functional, to calculate electronic structural properties up to a high precision degree. The alloys were composed with the concentrations x = 0.25, 0.5, and 0.75 in pursuance of 'special quasi-random structures' (SQS) approach of Zunger for the restoration of disorder around the observed site of alloys in the first few shells. The structural parameters have been predicted by minimizing the total energy in correspondence of unit cell volume. Our alloys established direct band gap at different concentrations that make their importance in optically active materials. Furthermore, density of states was discussed in terms of the contribution of Be and Mg s and chalcogen (S, Se, and Te) s and p states and observed charge density helped us to investigate the bonding nature. By taking into consideration of immense importance in optoelectronics of these materials, the complex dielectric function was calculated for incident photon energy in the range 0--15 eV. 展开更多
关键词 BexMgl-xX (X = s sE Te) alloys zinc-blende (ZB) phase density functional theory (DFT) electronic and optical properties
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[WS_(3)Cu_(2)]簇基超分子框的组装、结构及其三阶非线性光学响应
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作者 余蕙敏 王志康 +3 位作者 李洁 宋瑛林 杜明浩 郎建平 《无机化学学报》 SCIE CSCD 北大核心 2024年第1期71-78,共8页
将二(4-吡啶)硫烷(L_(1))、4,4'-二(4-吡啶)二苯甲酮(L_(2))分别与(Et_(4)N)(Tp*WS_(3))(A)(Tp*=三(3,5-二甲基吡唑)氢合硼酸根)和[Cu(Me CN)_(4)]PF_(6)进行反应,得到2个W/Cu/S簇基超分子化合物[Tp*WS_(3)Cu_(2)(L_(1))]_(2)(PF_(6... 将二(4-吡啶)硫烷(L_(1))、4,4'-二(4-吡啶)二苯甲酮(L_(2))分别与(Et_(4)N)(Tp*WS_(3))(A)(Tp*=三(3,5-二甲基吡唑)氢合硼酸根)和[Cu(Me CN)_(4)]PF_(6)进行反应,得到2个W/Cu/S簇基超分子化合物[Tp*WS_(3)Cu_(2)(L_(1))]_(2)(PF_(6))_(2)·2Me CN·2CHCl_(3)(1·2Me CN·2CHCl_(3))和[Tp*WS_(3)Cu_(2)(L_(2))(Me CN)]_(2)(PF_(6))_(2)·4Me CN (2·4Me CN)。对配合物1·2Me CN·2CHCl_(3)和2·4Me CN分别进行了单晶X射线衍射、核磁、质谱、红外、紫外可见和元素分析表征。单晶X射线衍射分析表明,它们是由2个L_(1)/L_(2)配体连接2个[Tp*WS_(3)Cu_(2)]~+簇核形成的阳离子型簇基超分子框。核磁氢谱和高分辨电喷雾离子化质谱(HRESI-MS)证明它们在溶液中具有一定的稳定性。并利用Z扫描技术测试了超分子化合物1·2Me CN·2CHCl_(3)和2·4MeCN溶液的三阶非线性光学特性,测试结果表明它们的三阶非线性光学响应强于前驱体A。 展开更多
关键词 W/Cu/s 超分子框 三阶非线性光学性质
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Strain effect on transport properties of hexagonal boron—nitride nanoribbons 被引量:1
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作者 陈风 陈元平 +1 位作者 张迷 钟建新 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期489-494,共6页
The transport properties of hexagonal boron-nitride nanoribbons under the uniaxial strain are investigated by the Green's function method. We find that the transport properties of armchair boron-nitride nanoribbon st... The transport properties of hexagonal boron-nitride nanoribbons under the uniaxial strain are investigated by the Green's function method. We find that the transport properties of armchair boron-nitride nanoribbon strongly depend on the strain. In particular, the features of the conductance steps such as position and width are significantly changed by strain. As a strong tensile strain is exerted on the nanoribbon, the highest conductance step disappears and subsequently a dip emerges instead. The energy band structure and the local current density of armchair boron nitride nanoribbon under strain are calculated and analysed in detail to explain these characteristics. In addition, the effect of strain on the conductance of zigzag boron-nitride nanoribbon is weaker than that of armchair boron nitride nanoribbon. 展开更多
关键词 transport properties hexagonal boron-nitride nanoribbons Green's function
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Several Properties of p-w-hyponormal Operators 被引量:1
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作者 LI Hai-ying YANG Chang-sen 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第2期195-201,共7页
In this paper, let T be a bounded linear operator on a complex Hilbert H. We give and prove that every p-w-hyponormal operator has Bishop's property(β) and spectral properties; Quasi-similar p-w-hyponormal operat... In this paper, let T be a bounded linear operator on a complex Hilbert H. We give and prove that every p-w-hyponormal operator has Bishop's property(β) and spectral properties; Quasi-similar p-w-hyponormal operators have equal spectra and equal essential spectra. Finally, for p-w-hyponormal operators, we give a kind of proof of its normality by use of properties of partial isometry. 展开更多
关键词 Aluthge transformation Bishop's property(β) quasi-similar w-hyponormal operators p-w-hyponormal operators
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First-principles investigation of electronic structure,effective carrier masses, and optical properties of ferromagnetic semiconductor CdCr_2S_4 被引量:1
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作者 朱旭辉 陈向荣 刘邦贵 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第5期346-351,共6页
The electronic structures, the effective masses, and optical properties of spinel CdCr_2S_4 are studied by using the fullpotential linearized augmented planewave method and a modified Becke–Johnson exchange functiona... The electronic structures, the effective masses, and optical properties of spinel CdCr_2S_4 are studied by using the fullpotential linearized augmented planewave method and a modified Becke–Johnson exchange functional within the densityfunctional theory. Most importantly, the effects of the spin–orbit coupling(SOC) on the electronic structures and carrier effective masses are investigated. The calculated band structure shows a direct band gap. The electronic effective mass and the hole effective mass are analytically determined by reproducing the calculated band structures near the BZ center.SOC substantially changes the valence band top and the hole effective masses. In addition, we calculated the corresponding optical properties of the spinel structure CdCr_2S_4. These should be useful to deeply understand spinel CdCr_2S_4 as a ferromagnetic semiconductor for possible semiconductor spintronic applications. 展开更多
关键词 CdCr2s4 semiconductor effective mass optical properties density functional theory
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