检索结果-南通市图书馆

Effects of Coal Rank and High Organic Sulfur on the Structure and Optical Properties of Coal-based Graphene Quantum Dots

引用

Acta Geologica Sinica(English Edition) 2018年第3期92卷 1218-1230页

作者： TANG Yuegang huan xuan LAN Chunyuan XU Miaoxin College of geoscience and Surveying Engineering China University of Mining & Technology (Beijing) Beijing 100083 China

Coal-based graphene quantum dots(GQDs) were successfully produced via a one-step chemical synthesis from six different coal ranks, from which two superhigh organic sulfur(SHOS) coals were selected as natural S-doped carbon sources for the preparation of S-doped GQDs. The effects of coal properties on coal-based GQDs were analyzed by means of high-resolution transmission electron microscopy(HRTEM), X-ray diffraction(XRD), Fourier transform infrared(FTIR) spectroscopy, X-ray photoelectron spectroscopy(XPS), ultraviolet-visible(UV-Vis) absorption spectroscopy, and fluorescence emission spectra. It was shown that all coal samples can be used to prepare GQDs, which emit bluegreen and blue fluorescence under ultraviolet light. Anthracite-based GQDs have a hexagonal crystal structure without defects, the largest size, and densely arranged carbon rings in their lamellae; the highrank bituminous coal-based GQDs are relatively reduced in size, with their hexagonal crystal structure being only faintly visible; the low-rank bituminous coal-based GQDs are the smallest, with sparse lattice fringes and visible internal defects. As the metamorphism of raw coals increases, the yield decreases and the fluorescence quantum yield(QY) initially increases and then decreases. Additionally, the surface of GQDs that were prepared using high-rank SHOS coal(high-rank bituminous coal) preserves rich sulfur content even after strong oxidation, which effectively adjusts the bandgap and improves the fluorescence QY. Thus, high-rank bituminous coal with SHOS content can be used as a natural S-doped carbon source to prepare S-doped GQDs, extending the clean utilization of low-grade coal.

关键词： coal graphene quantum dots coal rank organic sulfur China

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

EQUILIBRIUM REGULATION MODEL OF FOREST MANAGEMENT PERIOD AND APPLICATION EXAMPLES

引用

生物数学学报 1990年第1期5卷 10-15页

作者： xuan huan(Hunan college of Einance and Economics) 湖南财经学院湖南长沙

MODED The[I] in references gives age state aguation,Based on optimun control model of age regulation is constructured. in some system of forestry production. if a sort of tree is dovided into k ages and in intial peri... 详细信息

关键词： tree EQUILIBRIUM REGULATION MODEL OF FOREST MANAGEMENT PERIOD AND APPLICATION EXAMPLES

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Carbon steel anticorrosion performance and mechanism of sodium lignosulfonate

引用

Rare Metals 2024年第1期43卷 356-365页

作者： Bo-Kai Liao Rui-xuan Quan Ping-Xian Feng huan Wang Wei Wang Li Niu School of Chemistry and Chemical Engineering Guangzhou Key Laboratory of Sensing Materials and DevicesJoint Institute of Guangzhou University and Institute of Corrosion Science and TechnologyGuangzhou UniversityGuangzhou 510006China

Lignin is a typical biological macromolecule with a three-dimensional network structure and abundant functional groups. It has excellent ionic complexation ability and amphiphilic molecular structure *** this study, the carbon steel anticorrosion performance of sodium lignosulfonate(SLS) in an acid solution was evaluated using the weight loss method, electrochemical measurements, scanning vibration electrode technique(SVET), and surface characterization methods. SLS exhibited excellent corrosion inhibition efficiency for Q235carbon steel in 1 mol·L^(-1) HCl, reaching a maximum value of 98%. A low SLS concentration of 20 mg·L^(-1) resulted in the maximum corrosion inhibition efficiency, which remained nearly constant at higher SLS *** SVET test demonstrated that the formation of an SLS adsorption film can impede corrosion. This study confirms the significance of the application of green biomass resources in the field of metal corrosion protection and green functional materials.

关键词： Lignin Sodium lignosulfonate Corrosion inhibitor Carbon Steel

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Significant reduction of ammonia emissions while increasing crop yields using the 4R nutrient stewardship in an intensive cropping system

引用

Journal of Integrative Agriculture 2023年第6期22卷 1883-1895页

作者： ZHANG Chong WANG Dan-dan ZHAO Yong-jian XIAO Yu-lin CHEN huan-xuan LIU He-pu FENG Li-yuan YU Chang-hao JU Xiao-tang College of Tropical Crops Hainan UniversityHaikou 570228P.R.China College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193P.R.China

Ammonia (NH_3) emissions should be mitigated to improve environmental *** are one of the largest NH_3sources,they must be managed properly to reduce their emissions while achieving the target ***,we report the NH_3 emissions,crop yield and changes in soil fertility in a long-term trial with various fertilization regimes,to explore whether NH_3 emissions can be significantly reduced using the 4R nutrient stewardship (4Rs),and its interaction with the organic amendments (i.e.,manure and straw) in a wheat–maize *** the 4Rs significantly reduced NH_3 emissions to 6 kg N ha~(–1) yr~(–1) and the emission factor to 1.72%,without compromising grain yield (12.37 Mg ha~(–1) yr~(–1))and soil fertility (soil organic carbon of 7.58 g kg~(–1)) compared to the conventional chemical N *** using the 4R plus manure,NH_3 emissions (7 kg N ha~(–1) yr~(–1)) and the emission factor (1.74%) were as low as 4Rs,and grain yield and soil organic carbon increased to 14.79 Mg ha~(–1) yr~(–1) and 10.09 g kg~(–1),*** manure substitution not only significantly reduced NH_3 emissions but also increased crop yields and improved soil fertility,compared to conventional chemical N *** return exerted a minor effect on NH_3 *** results highlight that 4R plus manure,which couples nitrogen and carbon management can help achieve both high yields and low environmental costs.

关键词： ammonia emission crop yield 4R nutrient stewardship partial manure substitution winter wheat–summer maize cropping system

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

基于不同类型煤吸附甲烷的吸附势重要参数探讨

引用

煤炭学报 2015年第8期40卷 1859-1864页

作者：郇璇张小兵韦欢文河南省瓦斯地质与瓦斯治理重点实验室-省部共建国家重点实验室培育基地河南焦作454003 河南理工大学安全科学与工程学院河南焦作454003 河南理工大学瓦斯地质研究所河南焦作454003 南宁学院广西南宁530200

目前广泛使用的以饱和蒸汽压(P0)和吸附相密度(ρa)为重要参数的吸附势理论,在用于煤-甲烷吸附体系研究时,因求取虚拟饱和蒸汽压时参数k值选取随意,导致吸附行为描述精度不高。借助低中变质程度构造煤和共生非构造煤样品,通过开展煤对... 详细信息

目前广泛使用的以饱和蒸汽压(P0)和吸附相密度(ρa)为重要参数的吸附势理论,在用于煤-甲烷吸附体系研究时,因求取虚拟饱和蒸汽压时参数k值选取随意,导致吸附行为描述精度不高。借助低中变质程度构造煤和共生非构造煤样品,通过开展煤对甲烷等温吸附实验,进行P0和ρa标定,获得相应的吸附特征曲线,并在较宽温域内对不同类型煤等温吸附曲线进行预测。研究发现,基于k值的P0计算对吸附特征曲线影响较大,不同煤样的最优k值分别为kP1N=3.2,kP1D=3.4,kP8N=3.1,kP8D=3.0。利用313 K下吸附数据预测了不同煤在243,283,303,323 K的等温吸附曲线,认为选用Amankwah公式并利用最优k值计算P0时所获得结果与实测值吻合最好。

关键词：吸附势虚拟饱和蒸汽压吸附特征曲线最优k值

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Regulating Actuations and Shapes of Liquid Crystal Elastomers through Combining Dynamic Covalent Bonds with Cooling-Rate-Mediated Control

引用

Chinese Journal of Polymer Science 2024年第10期42卷 1442-1448,I0008页

作者： Ya-Wen Liu huan Liang Hong-Tu Xu En-Jian He Zhi-Jun Yang Yi-xuan Wang Yen Wei Zhen Li Yan Ji The Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing100084China Advanced Materials and Energy Center Academy of Aerospace Science and InnovationBeijing100088China

Realizing multiple locked shapes in pre-oriented liquid crystal elastomers(LCEs)is highly desired for diversifying deformations and enhancing ***,conventional LCEs only deform between two shapes for each actuation cycle upon liquid crystal-isotropic phase transitions induced by external ***,we propose to regulate the actuation modes and the locked shapes of a pre-orientated epoxy LCE by combining dynamic covalent bonds with cooling-rate-mediated *** actuation modes can be adjusted on demand by exchange reactions of dynamic covalent *** from the established actuation modes,such as elongation,bending,and spiraling,the epoxy LCE displays varied locked shapes at room temperature under different cooling *** mediums are utilized to control the cooling rate,including water,silicone oil,and copper *** approach provides a novel way for regulating the actuation modes and locked shapes of cuttingedge intelligent devices.

关键词： Liquid crystal elastomer Epoxy Dynamic covalent bond Vitrimer Cooling rate

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Medcheck:A novel software for automated de-formulation of traditional Chinese medicine(TCM)prescriptions by liquid chromatography-mass spectrometry

引用

Journal of Pharmaceutical Analysis 2024年第6期14卷 930-932页

作者： Xiao-lan Li Jian-qing Zhang Yun Li xuan-jing Shen huan-ya Yang Lin Yang Meng Xu Qi-rui Bi Chang-liang Yao De-an Guo Shanghai Research Center for Modernization of Traditional Chinese Medicine National Engineering Research Center of TCM Standardization TechnologyShanghai Institute of Materia MedicaChinese Academy of SciencesShanghai201203China b University of Chinese Academy of Sciences Beijing100049China

Prescriptions are the main clinical application of traditional Chinese medicines(TCMs).Common forms include Chinese patent medicines,Kampo formulas,and hospital decoctions.A new pre-scription called“famous classical formulas”is recently developed and expected to boom in the *** constituent me-dicinal plants in prescriptions is critical for new drug development and quality control[1],which could avoid safety issues from adulteration or substandard ingredients,as seen in the notorious Longdan Xiegan Pill event.

关键词： medicines formulation prescription

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

β-Receptor blocker enhances the anabolic effect of PTH after osteoporotic fracture

引用

Bone Research 2024年第2期12卷 302-313页

作者： Jie huang Tong Wu Yi-Rong Jiang xuan-Qi Zheng huan Wang Hao Liu Hong Wang Hui-Jie Leng Dong-Wei Fan Wan-Qiong Yuan Chun-Li Song Department of Orthopedics Peking University Third Hospital100191 BeijingChina Beijing Key Laboratory of Spinal Disease 100191 BeijingChina Engineering Research Center of Bone and Joint Precision Medicine 100191 BeijingChina

The autonomic nervous system plays a crucial role in regulating bone metabolism,with sympathetic activation stimulating bone resorption and inhibiting bone *** found that fractures lead to increased sympathetic tone,enhanced osteoclast resorption,decreased osteoblast formation,and thus hastened systemic bone loss in ovariectomized(OVX)***,the combined administration of parathyroid hormone(PTH)and theβ-receptor blocker propranolol dramatically promoted systemic bone formation and osteoporotic fracture healing in OVX *** effect of this treatment is superior to that of treatment with PTH or propranolol *** vitro,the sympathetic neurotransmitter norepinephrine(NE)suppressed PTH-induced osteoblast differentiation and mineralization,which was rescued by ***,NE decreased the PTH-induced expression of Runx2 but enhanced the expression of Rankl and the effect of PTH-stimulated osteoblasts on osteoclastic differentiation,whereas these effects were reversed by ***,PTH increased the expression of the circadian clock gene Bmal1,which was inhibited by NE-βAR ***1 knockdown blocked the rescue effect of propranolol on the NE-induced decrease in PTHstimulated osteoblast *** together,these results suggest that propranolol enhances the anabolic effect of PTH in preventing systemic bone loss following osteoporotic fracture by blocking the negative effects of sympathetic signaling on PTH anabolism.

关键词： blocker metabolism inhibited

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A widely used nonionic surfactant with desired functional groups as aqueous electrolyte additives for stabilizing Zn anode

引用

Rare Metals 2024年第8期43卷 3692-3701页

作者： Yue-Xian Song Xiao-Feng Wang Cai-Bin Liu Kai-xuan Guo Xu-huan Guo Xiao-Bin Zhong Yao-Hui Zhang Kai Wang Hui-Juan Guo Li-Xin Zhang Jun-Fei Liang School of Energy and Power Engineering North University of ChinaTaiyuan 030051China Key Laboratory of Green Chemical Process of Ministry of Education Hubei Key Laboratory of Novel Chemical Reactor and Green Chemical TechnologySchool of Chemical Engineering and PharmacyWuhan Institute of TechnologyWuhan 430073China Shanxi Provincial Key Laboratory for High Performance Battery Materials and Devices Taiyuan 030051China

Aqueous Zn-ion batteries(AZIBs) have emerged as potential candidates for Li-ion batteries due to their intrinsic safety and high ***,metallic Zn anodes encounter dendrite growth and water-induced corrosion,rendering poor stability and severe irreversibility at the electrode/electrolyte interface during *** stabilize the Zn anode,we report a low-cost and effective nonionic surfactant,Tween-20 polymer,as an electrolyte additive for *** Tween-20,sequential oxyethylene groups tended to be preferentially adsorbed on the Zn electrode to form a shielding layer for regulating uniform Zn ***,the hydrophobic hendecyl chains prevented H_(2)O-induced corrosion on the Zn anode *** from the desired functional groups,when only trace amounts of Tween-20(0.050 g·L^(-1)) were used,the Zn anode displayed good cycling stability over 2170 h at10 mA·cm^(-2) and a high average Coulombic efficiency of98.94% over 1000 *** Tween-20 polymer can also be effectively employed in MnO_(2)/Zn full *** their toxicity,price and amount of usage,these surfactant additives provide a promising strategy for realizing the stability and reversibility of high-performance Zn anodes.

关键词： Zn anode Dendrite growth Tween-20 polymer Surfactant additive Aqueous electrolyte

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

基于AM-OLED的汽车仪表显示

引用

电视技术 2012年第9期36卷 59-61,107页

作者：环翾黄舒平上海飞乐股份有限公司技术中心上海200072

分析了汽车仪表发展趋势,对AM-OLED与其他显示面板进行比较,提出了基于AM-OLED的汽车仪表显示方案。仪表信息经嵌入式处理器处理后以数字视频形式输出。FPGA接收视频信号,采用分形扫描方式控制AM-OLED面板显示图像。在AM-OLED上显示的... 详细信息

分析了汽车仪表发展趋势,对AM-OLED与其他显示面板进行比较,提出了基于AM-OLED的汽车仪表显示方案。仪表信息经嵌入式处理器处理后以数字视频形式输出。FPGA接收视频信号,采用分形扫描方式控制AM-OLED面板显示图像。在AM-OLED上显示的汽车仪表图像清晰度高、对比度强、色彩亮丽。

关键词： AM—OLED 分形扫描汽车仪表显示

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：