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基于格网尺度的新城区可持续空间形态要素测度研究——以宁波鄞州新城区为例 被引量:1
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作者 王肖惠 叶宇 +4 位作者 杨兰 王龙升 车茜 宋彦华 姚士谋 《热带地理》 CSCD 北大核心 2023年第10期1929-1939,共11页
基于城市形态学,提出良好的街道可达性、适宜的建设强度与建筑形态、足够的功能混合度是促进城市可持续发展的空间形态基础,以宁波市鄞州新城区为例,通过空间句法、空间矩阵、混合功能指标测度其城市空间形态要素,结果表明:1)鄞州新城... 基于城市形态学,提出良好的街道可达性、适宜的建设强度与建筑形态、足够的功能混合度是促进城市可持续发展的空间形态基础,以宁波市鄞州新城区为例,通过空间句法、空间矩阵、混合功能指标测度其城市空间形态要素,结果表明:1)鄞州新城区街道网络整体协同能力较强,建筑形态以中层板式及围合式、低层围合式、高层板式为主,单一功能用地占主导地位,完全混合用地仅占1.73%;2)鄞州新城区空间活力中值区占比最高,通过密度-形态关联性分析,其在多层高覆盖率的形态区间被屏蔽;3)功能混合、可达性、建筑强度及形态之间重合度较高,高容积率(>2.2)单元格中有64.54%聚集在可达性高值区,双功能、多功能混合单元有50.25%、85.71%聚集在可达性高值区,混合单元有公共设施用地时混合功能-可达性关联的效应更明显。 展开更多
关键词 可持续性 城市空间形态 格网尺度 空间活力 鄞州新城区
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Research on the Distribution of Incremental Benefits from the Entry of Collective Construction Land into the Market
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作者 Chenguang YUAN yanhua song +2 位作者 Ziwei WANG Lei WANG Xihui YANG 《Meteorological and Environmental Research》 CAS 2023年第5期29-30,共2页
In this paper,based on the process data of evaluating the benchmark land prices of collective construction land and agricultural land,the score of influencing factors is calculated,and a regression model between value... In this paper,based on the process data of evaluating the benchmark land prices of collective construction land and agricultural land,the score of influencing factors is calculated,and a regression model between value-added benefits and influencing factors is established.According to the contribution of the government and collectives to value-added benefits,the distribution proportions of different purposes and levels are calculated.The research results show that there are significant differences in the distribution proportion of value-added income among different levels.The government distribution proportion decreases with the decrease of level,while the collective distribution proportion increases with the decrease of level.For each level of decrease in commercial service industry land and industrial and mining warehousing industry land,the government distribution proportion decreases by an average of 2.66%and 2.34%,while the collective distribution proportion increases by an average of 2.66%and 2.34%,respectively.The average distribution proportion of the government in the value-added income of commercial service industry land is 31.58%,which is much higher than the average income of 23.68%in the value-added income of industrial and mining warehousing industry land. 展开更多
关键词 Collective construction land Value-added income Distribution proportion Influence factor Level
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以通用型化工学训工场和大型化工企业为基地开展本科实习教育的探索
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作者 宋艳华 高焓 +2 位作者 高岩 崔学军 袁晓玲 《大学化学》 CAS 2022年第7期53-56,共4页
化工生产实习是化工类专业教学的重要环节,旨在培养和提高学生实践动手能力。面对现在校企合作实习举步维艰的境地,提出了一种高校结合化工学训工场和大型化工企业为基地开展本科实习教育的模式,并就该模式的优势和效果进行了探讨,为推... 化工生产实习是化工类专业教学的重要环节,旨在培养和提高学生实践动手能力。面对现在校企合作实习举步维艰的境地,提出了一种高校结合化工学训工场和大型化工企业为基地开展本科实习教育的模式,并就该模式的优势和效果进行了探讨,为推动化工专业生产实习教学改革提供参考。 展开更多
关键词 化工生产实习 学训工场 化工企业 校–企–校合作
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具有超快电子传输能力的金/薄层氮化碳等离子光催化剂用于光催化产氢(英文) 被引量:3
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作者 莫曌 许晖 +7 位作者 陈志刚 佘小杰 宋艳华 严鹏程 徐远国 雷玉成 袁寿其 李华明 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第4期760-770,共11页
光催化产氢可以直接将太阳能转化为化学能,是非常有前景的产氢技术之一.然而,光催化产氢的瓶颈在于如何提高光催化产氢效率和光催化剂的稳定性,以及降低产氢成本.因此,开发廉价、易于制备的产氢光催化剂引起人们广泛关注.作为一种非金... 光催化产氢可以直接将太阳能转化为化学能,是非常有前景的产氢技术之一.然而,光催化产氢的瓶颈在于如何提高光催化产氢效率和光催化剂的稳定性,以及降低产氢成本.因此,开发廉价、易于制备的产氢光催化剂引起人们广泛关注.作为一种非金属半导体光催化剂,石墨相氮化碳(g-C_3N_4)具有良好的物理化学性质,如良好的化学和热稳定性、极佳的光电性能、强的抗氧化能力等.更为重要的是,g-C_3N_4具有合适的能带结构,能够利用可见光.因此,g-C_3N_4已广泛应用于光催化降解、空气净化、光解水和光催化CO2还原等领域.然而,体相g-C_3N_4仍然暴露出一些缺点,例如比表面积小、光生电子-空穴对的复合率高和反应动力学差等.将体相g-C_3N_4剥离成g-C_3N_4纳米薄片是提高光催化效率的有效方法.薄层g-C_3N_4纳米片具有较高的比表面积,比体相的g-C_3N_4有更好的光生电子-空穴对分离效率.为了进一步提高g-C_3N_4的光催化性能,本文通过在薄层g-C_3N_4表面均匀分散Au纳米颗粒来控制电荷载流子的流动.并通过光催化产氢和污染物降解来评估金/薄层氮化碳(Au/monolayer g-C_3N_4)复合材料的光催化性能.所有的Au/薄层g-C_3N_4复合材料均显示出优于体相g-C_3N_4的光催化性能,其中1%Au/薄层g-C_3N_4复合光催化剂具有最高的产氢速率(565μmol g.1h.1),且具有最佳的污染物降解能力.这主要归结于热电子的注入,而不是肖特基结.Au纳米颗粒的成功引入带来了表面等离子共振(SPR)效应,SPR效应不仅能够提高光吸收效率,而且能够带来高效的热电子转移途径.热电子是从Au纳米颗粒表面注入到薄层g-C_3N_4纳米片的导带上.因此,Au/薄层g-C_3N_4复合光催化剂具有更高的光生电子-空穴对迁移和分离效率,以及更低的光生电子-空穴对复合几率.采用紫外可见光谱(UV-Vis)、光致发光光谱(PL)、光电流和阻抗等表征手段研究了Au/薄层g-C_3N_4复合光催化剂性能提升的原因.结果表明,相比于薄层g-C_3N_4纳米片,Au/薄层g-C_3N_4复合光催化剂具有更好的光电性能,因而光催化活性更高.此外,与薄层g-C_3N_4纳米片的光电流强度相比,Au/薄层g-C_3N_4复合光催化剂的光电流强度没有发生改变,这表明薄层g-C_3N_4纳米片导带上的光生电子不可能转移到Au纳米颗粒的表面.也就是说,肖特基结并没有参与到电子转移过程中。 展开更多
关键词 单层氮化碳 金等离子纳米颗粒 光催化产氢 热电子 金/单层氮化碳
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C-I共掺杂多孔g-C_3N_4光催化分解水制氢(英文) 被引量:4
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作者 杨传锋 滕伟 +1 位作者 宋艳华 崔言娟 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第10期1615-1624,共10页
氢气是一种可替代传统燃料的理想清洁能源,利用光催化技术分解水制氢是制取氢气的有效途径之一。无机半导体光催化材料具有较高的活性和稳定性,且原料丰富,易加工改性.目前针对光催化技术的应用,大量的研究工作都集中在开发可见光响应... 氢气是一种可替代传统燃料的理想清洁能源,利用光催化技术分解水制氢是制取氢气的有效途径之一。无机半导体光催化材料具有较高的活性和稳定性,且原料丰富,易加工改性.目前针对光催化技术的应用,大量的研究工作都集中在开发可见光响应光催化剂,以提高对可见光的利用率.同时,非金属聚合物半导体因其特殊的光电性质,在光催化应用研究中越来越受到关注,如庚嗪基微孔聚合物(HMP)和共价三嗪基骨架(CTF).石墨相碳化氮(g-C_3N_4)是一种典型非金属二维聚合物半导体,被认为是一种非常有价值的光催化材料.然而,其较低的光生电子的传输效率限制了其实际应用,因此诸多研究对g-C_3N_4的物理化学结构进行优化,如半导体耦合、共聚合、纳米结构设计和掺杂.非金属掺杂是一种有效的方法,由于原子电负性差异引起的电荷分离可有效改善载流子传输效率,且保持半导体的非金属性质.通过O,B,P和S等掺杂可以扩大可见光响应范围,并调节能带位置以改善光催化活性.除了常见的单一非金属掺杂,金属和非金属元素或多非金属元素共掺杂的办法同样可提高g-C_3N_4的光催化性能.本工作通过两步法对双氰胺、尿素和碘化1-乙基-3-甲基咪唑的混合物直接热聚合,合成C-I共掺杂的多孔g-C_3N_4,其在可见光照射下表现出较高的产氢活性和稳定性.采用X射线衍射(XRD)、X射线光电子能谱(XPS)、荧光光谱(PL)和电化学实验等方法对多孔掺杂g-C_3N_4结构进行详细表征和分析.在助催化剂Pt和电子牺牲剂(三乙醇胺)存在的条件下,采用可见光(>400 nm)照射分解水产氢的方法评价其光催化活性.结果表明,后热处理和碘离子液掺杂对g-C_3N_4材料的结构和性能具有较大影响.C-I共掺杂和后热处理使催化剂产物颗粒尺寸减小,形成多孔片层状紧密堆积,比表面积和孔隙率显著增加,吸收带边发生蓝移.后热处理使样品层间距减小,聚合度增加,有利于电荷传输,C-I共掺杂后出现更多的缺陷,但没有改变其层状堆积的特性.XPS结果表明,样品中碘元素以I^-和I^(5+)的形式存在,改性后催化剂C/N比明显增加,sp^2芳环N含量增加,表面氨基含量降低,表明后热处理和C-I共掺杂没有改变多孔g-C_3N_4的基本骨架,共轭结构更加完善.PL和光电流结果表明,改性后样品的PL强度均显著降低,并且随着掺杂量的增加而逐渐降低,表明共掺杂可抑制光生电荷的复合.电化学测试结果表明,后热处理和C-I共掺杂的样品界面电荷转移电阻降低,导电率和电荷迁移率增加,从而有助于提高光催化性能.光解水产氢性能测试表明,后热处理和C-I共掺杂有利于催化剂产氢速率的提高,改性后CNIN_(0.2)的产氢速率达168.2μmol/h,是纯氮化碳的9.8倍.经过多次循环测试,其产氢性能保持稳定而没有显著下降,表明其产氢稳定性较好. 展开更多
关键词 多孔氮化碳 C-I共掺杂 后热处理 光催化 产氢
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Construction of 2D/2D Z-scheme MnO_(2-x)/g-C_(3)N_(4) photocatalyst for efficient nitrogen fixation to ammonia 被引量:3
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作者 Limin Yu Zhao Mo +6 位作者 Xianglin Zhu Jiujun Deng Fan Xu yanhua song Yuanbin She Huaming Li Hui Xu 《Green Energy & Environment》 SCIE CSCD 2021年第4期538-545,共8页
Reducing nitrogen to ammonia with solar energy has become a wide concern when it comes to photocatalysis research.It is considered to be one of the more promising alternate options for the conventional Haber-Bosch cyc... Reducing nitrogen to ammonia with solar energy has become a wide concern when it comes to photocatalysis research.It is considered to be one of the more promising alternate options for the conventional Haber-Bosch cycle.Herein,2D g-C_(3)N_(4)composites with modifying ultrathin sheet MnO_(2-x)were prepared and used as nitrogen fixation photocatalyst.With the assistance of the nature of MnO_(2-x),the generation rate of NH_(3)reached 225 mmol g^(-1)h^(-1),which is more than twice over the rate of pristine 2D g-C_(3)N_(4)(107 mmol g^(-1)h^(-1)).The presence of ultrathin sheet MnO_(2-x)shortens the gap of the carriers to the surface of photocatalyst.Thus the speed of electron transfer gets increased.Besides,the construction of Z-scheme heterojunction boosts the separation and migration of photogenerated carriers.As a result,the nitrogen reduction reaction(NRR)performance gets enhanced.The work may provide an example of promoting the NRR performance of non-metallic compound. 展开更多
关键词 Nitrogen fixation Z-Scheme heterojunction g-C_(3)N_(4) Photocatalysis
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ZnIn2S4@CNO多级纳米片用于光催化分解水制氢和还原CO2(英文) 被引量:2
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作者 祝凯 欧阳杰 +5 位作者 曾黔 孟苏刚 滕伟 宋艳华 唐盛 崔言娟 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第3期454-463,共10页
光催化分解水制氢和还原CO2是太阳能利用领域的研究热点,对清洁能源的转化具有重要意义.石墨相氮化碳(CN)作为一种非金属半导体,是一种非常有开发潜力的光催化材料.然而限于其聚合物本质,光催化效率仍有待进一步提高.原位非金属掺杂可... 光催化分解水制氢和还原CO2是太阳能利用领域的研究热点,对清洁能源的转化具有重要意义.石墨相氮化碳(CN)作为一种非金属半导体,是一种非常有开发潜力的光催化材料.然而限于其聚合物本质,光催化效率仍有待进一步提高.原位非金属掺杂可以利用元素电子结构调控电荷分布,优化光生电荷传输性能.同时,半导体复合,尤其是2D层状复合结构的构筑,可充分发挥2D半导体的优势,合适的能带交错有利于光生电荷的传输,可在一定程度上加速催化反应的进行.本文首先以草酸为氧掺杂源,采用二步煅烧法合成氧掺杂氮化碳纳米片催化剂(CNO).在二次煅烧和氧掺杂共同作用下,增大了CN层间距和多孔性,颗粒尺寸减小,同时增强了对光的吸光性,拓展了可见光吸收范围.接下来采用一步水热合成法得到ZnIn2S4@CNO(ZC)复合材料,在可见光照射下通过分解水制氢和CO2还原反应对复合材料进行光催化还原性能评价.采用X射线衍射(XRD)、透射电镜(TEM)、X射线光电子能谱(XPS)、荧光光谱(PL)、光电化学测试等方法对ZC进行详细的结构表征和分析.XRD和XPS结果表明,经过一步直接水热可得到层状ZC复合材料,高倍TEM进一步证实二者形成均一的2D异质复合材料.N2-吸附-脱附曲线表明,复合材料具有较大的比表面积和均一的孔结构分布,主要得益于O掺杂CNO纳米片的多孔性结构.光电性质测试结果表明,相比于CNO,复合材料具有降低的荧光发射强度和延长的荧光寿命,表明复合产物显著抑制了光生电荷的复合.电化学测试进一步表明,复合异质结的构筑有利于光生载流子的产生,同时降低了界面电荷转移电阻,提高了电荷迁移速率.因此,多孔2D异质结构的构筑对促进CN基半导体光催化还原具有重要作用.在可见光照射下(λ>400 nm),复合材料表现出优异的光催化还原性能,且随着CNO含量的增加催化活性不断提高,其中ZC 40%(CNO质量比40%)具有最佳的催化活性,其产氢速率达188.4μmol/h,约是ZnIn2S4和CNO的2.1倍.同时,光催化还原CO2测试表明,复合材料具有显著提高的CO和CH4产率,其中CO为主要反应产物.ZC40%的CO产生速率为12.69μmol/h,分别是ZnIn2S4和CNO的2.2倍和14.0倍.对催化剂进行连续光反应,结果表明,复合催化剂具有优异的结构稳定性和活性稳定性,能够持续发生光还原反应制取H2和CO. 展开更多
关键词 ZnIn2S4 氧掺杂氮化碳 光催化 产氢 CO2还原
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Improvement of Evaluation Methods for Cultivated Land Quality 被引量:3
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作者 yanhua song Xihui YANG 《Asian Agricultural Research》 2018年第10期57-62,共6页
As the existing cultivated land quality evaluation index system is unable to accurately evaluate the quality of cultivated land after land remediation,a modified land use coefficient method was established in this stu... As the existing cultivated land quality evaluation index system is unable to accurately evaluate the quality of cultivated land after land remediation,a modified land use coefficient method was established in this study to calculate the land use coefficient of cultivated land after land remediation. An evaluation index system was first established for the land utilization level of cultivated land in the remediation areas.After that,the land utilization level index before and after the remediation was evaluated separately. The ratio of the two was used as the correction factor to correct the original land use coefficient. The corrected land use coefficient was used to evaluate the quality of cultivated land. The quality evaluation and verification of the land remediation areas in Yuzhou City were conducted. It was found that the land use coefficient corrected by the modified method was more consistent with that calculated by production method 5 years after the project acceptance. It suggests that the modified land use coefficient method reflects the impact of land remediation on the quality of cultivated land,and it is more suitable compared with the production method for the quality evaluation of cultivation land in remediation areas. 展开更多
关键词 耕地 质量评价指标体系 农业 发展现状
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Study on Ecological Carrying Capacity of Land in Henan Province
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作者 yanhua song Lei WANG Xihui YANG 《Meteorological and Environmental Research》 CAS 2022年第4期40-47,50,共9页
In order to explore the technical methods to improve the ecological carrying capacity of regional land under the premise of limited land use area,an open ecological footprint model is established based on the traditio... In order to explore the technical methods to improve the ecological carrying capacity of regional land under the premise of limited land use area,an open ecological footprint model is established based on the traditional ecological footprint model.Using the two models,this paper evaluates the ecological carrying capacity of Henan Province in 2017.The results indicate that the ecological productive footprint of cultivated land in Henan Province is much larger than the ecological carrying capacity,but the ecological consumption footprint is lower than the ecological carrying capacity.The open ecological footprint model can clearly distinguish the internal and the external ecological consumption footprint after corrected by the consumption adjustment coefficient and the land-use structure adjustment coefficient.Based on the open ecological footprint model,the ecological carrying capacity evaluation results of Henan Province are more realistic.The comprehensive ecological carrying capacity in Henan Province has a surplus,but there are significant differences among different land use types.The cultivated land has the largest ecological carrying capacity surplus,while the fossil energy land has a larger ecological carrying capacity deficit.In the process of achieving sustainable development,Henan Province should focus on reducing energy consumption and improving the ecological carrying capacity of fossil energy land.The paper concludes that the open ecological footprint model can simulate the ecological carrying capacity under different land use structures and different consumption structures.According to the simulation results,the technical methods to improve the ecological carrying capacity under the premise of limited land use scale can be proposed.The research can provide reference for land use structure adjustment,land use planning and land protection in Henan Province.It can also provide scientific basis for ecological protection and high-quality development of the Yellow River basin. 展开更多
关键词 Ecological footprint Ecological carrying capacity Open model Consumption adjustment coefficient Land-use structure adjustment coefficient
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Study on the Theory and Method of Real Estate Property Right Appraisal
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作者 Chenguang YUAN Ziwei WANG +2 位作者 yanhua song Yan TIAN Jianbo YANG 《Meteorological and Environmental Research》 CAS 2022年第6期9-10,共2页
This paper first introduces the overview of real estate appraisal theory,the basic situation of real estate appraisal,the basic principles and characteristics of real estate appraisal,and three main appraisal methods.... This paper first introduces the overview of real estate appraisal theory,the basic situation of real estate appraisal,the basic principles and characteristics of real estate appraisal,and three main appraisal methods.On this basis,the specific use scope of each method,the meaning of each parameter,and the influencing factors are analyzed.Then,based on the in-depth study of various existing appraisal theories and methods,a new appraisal method is proposed:the appraisal analysis method based on fuzzy analytic hierarchy process. 展开更多
关键词 Real estate property right appraisal Market comparison method Cost method Capitalized earnings method Fuzzy analytical hierarchy process
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Study on"Same Land,Same Right,Same Price"of Collective Commercial Construction Land and State-owned Land
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作者 Chenguang YUAN Ziwei WANG +2 位作者 yanhua song Lei WANG Xihui YANG 《Meteorological and Environmental Research》 CAS 2022年第5期45-46,55,共3页
Taking Changyuan City of Henan Province,a pilot city of collective commercial construction land reform,as the research object,this paper analyzes the scientific connotation of"same land,same right,same price"... Taking Changyuan City of Henan Province,a pilot city of collective commercial construction land reform,as the research object,this paper analyzes the scientific connotation of"same land,same right,same price"of collective commercial construction land and state-owned land in the unified urban-rural construction land market system,and how to realize"same land,same right,same price".The results show that in order to realize the fair entry of collective construction land into the market,it must base on scientific use control,unify the urban and rural construction land market and adhere to the guidance of market mechanism,and finally realize the sustainable development of the land market. 展开更多
关键词 Collective commercial construction land Same land Same right Same price Land market
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Research on Dynamic Change of Regional Cultivated Land Quality and Its Influence Factors
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作者 Ziwei WANG Lingchao WANG +1 位作者 yanhua song Yan TIAN 《Meteorological and Environmental Research》 CAS 2021年第5期77-83,共7页
According to the reason of quality change,cultivated land is divided into four change types: decrease,increase,land construction project and gradual change. Farmland grading factor method is used to evaluate the quali... According to the reason of quality change,cultivated land is divided into four change types: decrease,increase,land construction project and gradual change. Farmland grading factor method is used to evaluate the quality of cultivated land in Zhengzhou City. The results show that(1) the quality of cultivated land in Zhengzhou City has slightly increased during the study period. Due to the decrease in the amount of cultivated land,the production capacity has declined.(2) The impact of different types of cultivated land change on the quality of regional cultivated land is in the order of gradual change> decrease > increase > land construction project.(3) Zhengzhou City is able to maintain the quality of regional cultivated land through new cultivated land and project construction,but fails to maintain the production capacity. By analyzing the mechanism of regional cultivated land quality change in different types,the relationship between quality changes in various types of areas and overall quality changes could be analyzed,and it could provide policy recommendations for managers to formulate farmland quality and capacity protection,with significant application value. 展开更多
关键词 Regional cultivated land quality Driving mechanism Mutation area Gradient area Zhengzhou City
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A Facile Synthesis and Photoluminescence Properties of SiO<sub>2</sub>:Tb<sup>3+</sup>Spherical Nanoparticles
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作者 Murad M. A. Abualrejal Haifeng Zou +2 位作者 Jie Chen yanhua song Ye Sheng 《Advances in Nanoparticles》 2017年第2期11-21,共11页
Controlled synthesis of functional photoluminescent materials are of particular interest due to their fascinating optical properties. Herein, highly uniform SiO2:xTb3+spherical nanoparticles are fabricated by a facile... Controlled synthesis of functional photoluminescent materials are of particular interest due to their fascinating optical properties. Herein, highly uniform SiO2:xTb3+spherical nanoparticles are fabricated by a facile sol-gel method. The structure, morphology, compositions, and luminescence properties of As-prepared samples were well investigated using TEM, SEM, EDX, XRD, XPS and luminescence spectroscopy. The PL intensity of SiO2:xTb3+spherical nanoparticles is Tb3+ ions concentration dependent achieved a maximum at 3 mol % of Tb3+. Particularly, SiO2:xTb3+spherical nanoparticles exhibit a green emission corresponding to 5D4→7Fj transition (541 nm) of Tb3+. These results show that As-prepared phosphors may find potential application in solid-state lighting fields. 展开更多
关键词 Silica SOL-GEL PHOTOLUMINESCENCE TERBIUM Doped-Silica
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Electrospinning Synthesis and Photoluminescence Properties of One-Dimensional SiO<sub>2</sub>:Tb<sup>3+</sup>Nanofibers and Nanobelts
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作者 Murad M. A. Abualrejal Haifeng Zou +2 位作者 Jie Chen yanhua song Ye Sheng 《Advances in Nanoparticles》 2017年第2期33-47,共15页
Controlled synthesis of functional photoluminescent materials is of particular interest due to their fascinating optical properties. Herein, highly uniform one-dimensional (1D) SiO2:xTb3+ nanofibers and nanobelts are ... Controlled synthesis of functional photoluminescent materials is of particular interest due to their fascinating optical properties. Herein, highly uniform one-dimensional (1D) SiO2:xTb3+ nanofibers and nanobelts are fabricated by electrospinning method combined with sol-gel method. The as-prepared SiO2:xTb3+ nanofibers are belt-like morphology after calcination. The formation mechanism of SiO2:xTb3+ nanofibers and nanobelts is proposed based on decomposition of polyvinylpyrrolidone (PVP) and crystallization of SiO2. The photoluminescence (PL) intensity of SiO2:xTb3+ nanofibers and nanobelts is Tb3+ ions concentration dependent with a maximum at 4 mol% of Tb3+. Particularly, SiO2:xTb3+ nanofibers and nanobelts exhibit a green emission corresponding to 5D4 → 7Fj transition (541 nm) of Tb3+. 展开更多
关键词 Silica ELECTROSPINNING PHOTOLUMINESCENCE Terbium Doped-Silica
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Study on Division Method of Quality Monitoring Control Area Based on Comprehensive Cultivated Land Attribute
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作者 Ziwei WANG Lingchao WANG +3 位作者 yanhua song Chenguang YUAN Lei WANG Xihui YANG 《Meteorological and Environmental Research》 CAS 2022年第6期84-87,共4页
The quality change of cultivated land resources requires the scientific deployment of monitoring areas.In this study,Yuzhou City is taken as an example to divide the quality monitoring control areas through the study ... The quality change of cultivated land resources requires the scientific deployment of monitoring areas.In this study,Yuzhou City is taken as an example to divide the quality monitoring control areas through the study of natural quality,utilization level,income level,and utilization characteristics,etc.Compared with the traditional administrative unit division or cultivated land quality division method,the regional homogeneity of this study is stronger,and there are quality differences between regions.It provides precondition and precision guarantee for the monitoring of cultivated land quality. 展开更多
关键词 Cultivated land quality monitoring Control area DIVISION Cultivated land attribute
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Balance of Urban Benchmark Land Price in Henan Province:A Case Study of Residential Land
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作者 Yan TIAN Fei TENG +3 位作者 yanhua song Lei WANG Xihui YANG Qingwei YANG 《Meteorological and Environmental Research》 CAS 2022年第5期36-39,44,共5页
Benchmark land price balance is an important content of urban benchmark land price work.In this paper,by building different levels of factor layers,the balance of urban residential land in 18 cities of Henan Province ... Benchmark land price balance is an important content of urban benchmark land price work.In this paper,by building different levels of factor layers,the balance of urban residential land in 18 cities of Henan Province is studied,and the 18 cities can be divided into five categories.It is found that the urban land price level is basically consistent with the level of economic development,and some urban land price is lower due to local policy. 展开更多
关键词 Benchmark land price BALANCE Residential land Henan Province
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Early Warning of Cultivated Land Quality Based on Multiple Indicators
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作者 Ziwei WANG Lingchao WANG +1 位作者 yanhua song Yan TIAN 《Meteorological and Environmental Research》 CAS 2022年第6期78-83,87,共7页
At present,the quality protection and early warning of cultivated land in China are actually based on the increase and decrease of the quantity of cultivated land and the change of its quality.The early warning of cul... At present,the quality protection and early warning of cultivated land in China are actually based on the increase and decrease of the quantity of cultivated land and the change of its quality.The early warning of cultivated land quality based on this is easy to cause the problem of missing and wrong alarm.Based on the quality and productivity change of regional cultivated land,early warning on the regional cultivated land quality is conducted in this study respectively,and the results of the two early warning are compared.Moreover,a multi-indicator cultivated land quality early warning based on the quality change,productivity change and auxiliary indicators is proposed.The results show that:early warning of cultivated land quality based on quality and productivity change of cultivated land has certain limitations.Based on multi-indicator early warning,the number of counties with heavy,medium and light warnings in Henan Province is 52,8 and 11 respectively.The multi-indicator early warning result of cultivated land quality is more accurate,which can provide a basis for cultivated land protection and management assessment,and has great application value. 展开更多
关键词 Early warning of cultivated land quality Cultivated land productivity Cultivated land protection Henan Province
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Design of Trinity Framework for Cultivated Land Protection
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作者 Ziwei WANG Yan TIAN +1 位作者 Lingchao WANG yanhua song 《Asian Agricultural Research》 2021年第11期32-35,共4页
Starting with the goals and tasks of quantity,quality and ecological protection in different scales,this paper constructs a"trinity"framework of cultivated land protection system,and puts forward the key poi... Starting with the goals and tasks of quantity,quality and ecological protection in different scales,this paper constructs a"trinity"framework of cultivated land protection system,and puts forward the key points of cultivated land protection in different scales.Finally,a preliminary evaluation is made on the quantity,quality and ecological protection of cultivated land on a macro scale in China. 展开更多
关键词 Cultivated land protection Quantity QUALITY ECOLOGY
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Distribution of Land Increment Income from Marketing Rural Collective Land for Development Purposes : A Case Study of Changyuan City
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作者 Chenguang YUAN Lingchao WANG +2 位作者 yanhua song Ziwei WANG Yan TIAN 《Asian Agricultural Research》 2021年第10期31-36,共6页
In order to protect the property rights and interests of farmers,promote the revitalization and development of rural areas,and provide a reference basis for the reform of marketing rural collective land for developmen... In order to protect the property rights and interests of farmers,promote the revitalization and development of rural areas,and provide a reference basis for the reform of marketing rural collective land for development purposes,this study explores the reasonable distribution proportion of land increment income from marketing rural collective land for development purposes through analytic hierarchy process and Delphi expert scoring method.The results show that there is a positive correlation between land increment income and land grade,that is,the higher the land grade,the higher the increment income,the larger the proportion of increment income to the transaction price.According to the calculation,when marketing rural collective land for development purposes,the reasonable distribution proportion of the land increment income of the government and the village collective is 28.6%and 71.4%,respectively,and the land increment income actually obtained by farmers has been greatly improved compared with the current situation.In practice,this distribution model has universal applicability and long-term mechanism.The reform of marketing also needs to improve the standard of marketing,explore diversified channels to protect interests,and strengthen the construction of rural collective management system.In short,the distribution of land increment income from marketing rural collective land for development purposes should proceed from the perspective of land property rights and the factors affecting the price of collective land for development purposes,in order to build a reasonable income distribution model. 展开更多
关键词 Rural collective land for development purposes Land increment income Rational distribution Analytic hierarchy process
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A candy-like photocatalyst by wrapping Co, N-co-doped hollow carbon sphere with ultrathin mesoporous carbon nitride for boosted photocatalytic hydrogen evolution
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作者 Jinyuan Liu Shumin Zhu +7 位作者 Bin Wang Ruizhe Yang Rong Wang Xingwang Zhu yanhua song Junjie Yuan Hui Xu Huaming Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第2期367-371,共5页
Hierarchical carbon material is used as a star cocatalyst in the field of photocatalysis due to its excellent catalytic properties. In this work, mesoporous carbon nitride sheet(MCNS) photocatalyst introduced nitrogen... Hierarchical carbon material is used as a star cocatalyst in the field of photocatalysis due to its excellent catalytic properties. In this work, mesoporous carbon nitride sheet(MCNS) photocatalyst introduced nitrogen-doped hollow carbon spheres assembled with cobalt nanoparticles(Co@NHC) is synthesized by electrostatic adsorption. A series of characterizations are analyzed to display the structures, morphologies and optical properties of as-prepared materials. The photocatalytic activity of Co@NHC/MCNS material is evaluated with hydrogen evolution under visible light irradiation. The results indicate that 5 wt%Co@NHC/MCNS material reveals higher photocatalytic activity of hydrogen evolution rate of 3675 μmol/g with 4 h reaction time, which is 159 times than that of pure MCNS material. The carbon material with excellent charge transport properties can effectively accelerate the charge transfer from ultrathin MCNS to cobalt nanoparticles. The goal of improving the photocatalytic performance of Co@NHC/MCNS material is achieved. As a result, it provides a feasible and promised approach for doping transition metals to enhance photocatalytic activity. 展开更多
关键词 Candy-like photocatalyst Mesoporous carbon nitride Hollow carbon spheres Photocatalytic hydrogen evolution
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