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水棘针营养器官构造研究
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作者 黄珊珊 张宝憬 +1 位作者 刁云鹏 许亮 《吉林医药学院学报》 2012年第3期150-151,共2页
水棘针Amethystea caerulea L.为唇形科多年生芳香草本植物.直立多分枝,单叶对生,通常3全裂,稀5深裂,裂片披针形至卵状披针形,叶缘有粗大锯齿,呈散的聚伞花序排成圆锥状;萼钟形,萼齿带蓝色,花冠小,长约3~4毫米,唇形5裂,蓝色雄蕊4个,前... 水棘针Amethystea caerulea L.为唇形科多年生芳香草本植物.直立多分枝,单叶对生,通常3全裂,稀5深裂,裂片披针形至卵状披针形,叶缘有粗大锯齿,呈散的聚伞花序排成圆锥状;萼钟形,萼齿带蓝色,花冠小,长约3~4毫米,唇形5裂,蓝色雄蕊4个,前雄蕊能育,小坚果褐色,具网状皱纹. 展开更多
关键词 水棘针 营养器 官构
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Morphological,Anatomical and Genetic Analysis for a Rice Mutant with Abnormal Hull 被引量:6
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作者 张全芳 徐建第 +3 位作者 李云 徐培州 张红宇 吴先军 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第6期519-526,共8页
A mutant with abnormal hull was first discovered from a twin-seedling strain W2555 in rice (Oryza sativa L.). The mutant had sparse branches and decreased number of florets from the base to the peak. Frequently, the... A mutant with abnormal hull was first discovered from a twin-seedling strain W2555 in rice (Oryza sativa L.). The mutant had sparse branches and decreased number of florets from the base to the peak. Frequently, the florets at the top of the panicle did not develop completely. The underdeveloped florets often showed slender and white in their life cycle. Genetic analysis indicated that the mutant traits were controlled by a single recessive gene (temporarily designated as ah). ah gene controlled the development of inflorescence meristem and the flower organ. The florets of mutant showed degenerated lemma and palea. Stamens and lodicules were homeoticly transformed into pistils and palea/lemma-like structures, respectively. It seemed that ah mutant phenotypes of the homeotic conversions in lodicules and stamens were very similar to that of the B loss-of-function spwl gene reported previously in rice. 展开更多
关键词 Rice (Oryza sativa L.) ah mutant floral organ anatomical structure genetic analysis
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Correlation between Texture and Sensory Evaluation of Labadou 被引量:1
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作者 李清明 蔡霞 +1 位作者 蒋立文 陶湘林 《Agricultural Science & Technology》 CAS 2014年第1期159-161,165,共4页
[Objective] The aim was to measure hardness and chewiness of Labadou with a texture analyzer and explore correlation of hardness and chewiness with quality by sensory evaluation. [Method] Labadou underwent compression... [Objective] The aim was to measure hardness and chewiness of Labadou with a texture analyzer and explore correlation of hardness and chewiness with quality by sensory evaluation. [Method] Labadou underwent compression, puncture, shearing and batch compression with four probes (P/100, P/2, A/LKB-F and A/BE) and sensory evaluation was made on Labadou as per Nine Point Calibration Method. Specifical y, chewiness measured by batch compression was taken as an independent variable and hardness as a dependent variable to get a prediction model of Labadou hardness by model fitting. [Result] The ideal parameters of Labadou included probe at A/BE, test speed at 1.0 mm/s, and strain at 70%. The chewiness was of extremely significant correlation with hardness (r=0.92, P〈0.01). [Conclusions] The detecting method could detect distinct texture of different Labadou accurately and expediently. 展开更多
关键词 Labaclou TEXTURE CORRELATION Sensory evaluation
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Surface chemistry of MXene quantum dots:Virus mechanism-inspired mini-lab for catalysis 被引量:1
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作者 Yuhua Liu Wei Zhang Weitao Zheng 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第11期2913-2935,共23页
Scientific research is currently more interdisciplinary.Researchers have parsed the surface structure of virus,constructed the interaction model of virus-receptors,offering the clues for studying efficient targeted dr... Scientific research is currently more interdisciplinary.Researchers have parsed the surface structure of virus,constructed the interaction model of virus-receptors,offering the clues for studying efficient targeted drugs.Likewise,catalysis is also highly relevant to modern human life.Exploring the surface structure and physicochemical properties of catalysts is of great significance for the design of efficient catalysts.Great progresses have been made for endowing specific physicochemical properties of catalysts through controlling the size of materials and coordination chemistry of active sites,particularly at nanometer scale since Sir John Meurig Thomas and Tao Zhang’s early ground-breaking contribution,with casting on a very surface issue.Herein,functional regulation renders the emerging MXene quantum dots(MQDs)excel in contrast to the typical carbon-based quantum dots.In fact,similar to the interaction of virus-receptors model,the surface functional groups decorated MQDs provide a mini-lab to afford a variety of adjustments,involved with the type modification and electronic structure tuning of groups as well as their arrangement,together with the interaction between the groups and active materials/support,ultimately for packaging or designing high-activity catalysts. 展开更多
关键词 Surface chemistry Functional group Structure characterization MXene Quantum dot
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Effects of different periods of renal ischemia on liver as a remote organ 被引量:5
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作者 Mehri Kadkhodaee Fereshteh Golab +5 位作者 Maryam Zahmatkesh Rana Ghaznavi Mehdi Hedayati Hossein Ali Arab Seyed Naser Ostad Manoocher Soleimani 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第9期1113-1118,共6页
AIM:To assess the hepatic changes after induction of different periods of renal ischemia. METHODS:Rats were subjected to either sham operation or ischemia (30,45 and 60 min) followed by 60 min reperfusion. Liver and r... AIM:To assess the hepatic changes after induction of different periods of renal ischemia. METHODS:Rats were subjected to either sham operation or ischemia (30,45 and 60 min) followed by 60 min reperfusion. Liver and renal functional indices were measured. Hepatic glutathione (GSH) and ferric reducing antioxidant power levels and the concentration of interleukin (IL)-10 and tumor necrosis factor (TNF-α) were evaluated. Portions of liver and kidney tissues were fixed for histological evaluation. RESULTS:Forty-five minutes renal ischemia followed by 60 min reperfusion caused significant changes in liver structure and a significant reduction in renalfunction. These rats showed a significant decrease in liver GSH,as well as a significant increase in TNF-α and IL-10 concentrations. These results demonstrated that renal ischemia caused changes in liver histology,function,oxidative stress and inflammatory status,which led to a reduction in hepatic antioxidant capacity. With 30 min ischemia,the magnitude of these changes was less than those with 45 or 60 min ischemia.CONCLUSION:A minimum of 45 min ischemia is needed to study the effects of renal injury on the liver as a remote organ. 展开更多
关键词 Renal ischemia LIVER Remote organ Oxidative stress INFLAMMATION
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CO_2/CH_4 and CH_4/N_2 separation on isomeric metal organic frameworks 被引量:6
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作者 Xiaoqing Wang Libo Li +1 位作者 Jiangfeng Yang Jinping Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第12期1687-1694,共8页
Two isomeric metal-organic frameworks(MOFs) with 2-dimensional(2D) and 3-dimensional(3D) topologies both comprised of Cu(Ⅱ) and OTf(OTf = trifluoromethanesulfonate) ions were synthesized and characterized.The CO_2,CH... Two isomeric metal-organic frameworks(MOFs) with 2-dimensional(2D) and 3-dimensional(3D) topologies both comprised of Cu(Ⅱ) and OTf(OTf = trifluoromethanesulfonate) ions were synthesized and characterized.The CO_2,CH_4 and N_2 adsorption properties of the two isomeric MOFs were investigated from 263 K to 298 K at0.1 MPa.The results showed that the 2D MOF exhibited a higher selectivity for CO_2 from CO_2/CH_4 and CH_4from CH_4/N_2 compared to the 3D MOF,even though it possessed a lower surface area and pore volume.The higher adsorption heats of gases on the 2D MOF inferred the strong adsorption potential energy in the layered MOFs.Dynamic separation experiments using CO_2/CH_4 and CH_4/N_2 mixtures on the two MOFs proved that the2 D MOF had a longer elution time than the 3D MOF as well as better separation abilities. 展开更多
关键词 Metal–organic frameworks Isomeric frameworks Adsorption Separation
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Insight into the structural features of organic species in Fushun oil shale via thermal dissolution 被引量:3
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作者 Shengkang Wang Xianyong Wei Zhimin Zong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第10期2162-2168,共7页
Fushun oil shale(FOS) was subjected to thermal dissolution(TD) under different conditions. The results show that the optimal solvent, temperature, time, and ratio of solvent to FOS are ethanol, 300 °C, 2 h, and 5... Fushun oil shale(FOS) was subjected to thermal dissolution(TD) under different conditions. The results show that the optimal solvent, temperature, time, and ratio of solvent to FOS are ethanol, 300 °C, 2 h, and 5 ml·g^(-1),respectively and the corresponding yield of the soluble portion(SP) is 32.2%(daf), which is much higher than the oil content of FOS(ca. 6%), suggesting that TD in ethanol is an excellent way to extract organics from FOS.According to 3 direct analyses, aliphatic moieties in FOS are the most abundant followed by C\\O-containing moieties and each cluster in FOS has 3 conjugated aromatic rings on average with fewer substituents. According to the analysis with a gas chromatograph/mass spectrometer, alkanes are predominant in all the SPs. A number of alkenes were identified in the SPs from the TD, while none of the alkenes were detected in acetone-SP obtained at room temperature, implying that the TD can destroy the π-π and intertwining interactions between alkenes and macromolecular structures in FOS. Moreover, a small amount of alkyl-substituted phenols and alkoxysubstituted phenols were detected in ethanol-SP from the TD, which could be the products from ethanolyzing the macromolecular moiety of FOS. 展开更多
关键词 Oil shale Structural feature Thermal dissolution
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Bodies, Persons, and Respect for Humanity: A Kantian Look at the Permissibility of Organ Commerce and Donation
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作者 Lina Papadaki 《Journal of Philosophy Study》 2013年第6期456-469,共14页
Can choosing to sale one's kidney be morally permissible? "No", Kant would answer. Humanity, whether in one's own person or that of any other, must never be treated merely as a means, but always at the same time ... Can choosing to sale one's kidney be morally permissible? "No", Kant would answer. Humanity, whether in one's own person or that of any other, must never be treated merely as a means, but always at the same time as an end, is Kant's instruction (Groundwork 4:429). He thought that organ sale violates this imperative. Lectures on Ethics (27:346) shows that "... a man is not entitled to sell his limbs for money If a man does that, he turns himself into a thing, and then anyone may treat him as they please, because he has thrown his person away...." This paper explains Kant's reasons against commerce in organs, drawing on his views on prostitution, and the moral impermissibility of sexual use within this context, a case which he himself compares to the selling of one's body part(s). Can choosing to donate one's kidney be morally permissible? If we take Kant's views at face value, it would follow that organ donation is on a par with morality only if it takes place in a context where people have gained rights over each other's persons (for example, in a marital context). In this context, however, a person has a right to her partner's kidney should she happen to need it, which can open the path to bodily violation. Moreover, this view severely restricts the permissibility of organ donation. In this paper, I argue that a closer examination of Kant's views on what is involved in the idea of respecting humanity could reveal that organ donation does not violate the categorical imperative. In fact, it could be said to follow from such an imperative that we actually have a duty to organ donation. 展开更多
关键词 Kant organ donation organ sale PROSTITUTION
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Comparison of Sensory Characteristics of Green Tea Produced in Thai Nguyen and Phu Tho Province, Vietnam 被引量:1
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作者 Dang Thi Minh Luyen Ha Duyen Tu +2 位作者 Philippe Lebailly Nguyen Duy Thinh Tu Viet Phu 《Journal of Food Science and Engineering》 2014年第2期107-114,共8页
Green tea is a popular product with a high consumption in Vietnam. Moreover, green tea produced in Tan Cuong commune, Thai Nguyen province, has long been recognized for its superior quality to those coming from other ... Green tea is a popular product with a high consumption in Vietnam. Moreover, green tea produced in Tan Cuong commune, Thai Nguyen province, has long been recognized for its superior quality to those coming from other regions of the country. This study aims at comparing the tea from Thai Nguyen and Phu Tho and finding out if the difference can be identified through sensory analysis. Two products picked from Tan Cuong, Thai Nguyen province, and two others from Phu Ho district, Phu Tho province were evaluated by a trained panel of 12 judges (11 women and 1 man). The sensory evaluation of the dry tea (11 descriptors) was carried out separately from the brewed tea (21 descriptors) and brewed leaf (five descriptors) using an unstructured intensity scale (10 cm). Statistic analyses have shown differences between regions in all three groups of attributes: dry leaf, liquor and brewed leaf. 展开更多
关键词 Green tea sensory analysis.
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Properties and organic activation of ocean clay in the East Pacific
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作者 Peiping Zhang Xiaoguo Chi +3 位作者 Chunyan Tian Baojun Wang Huahua Lü Xuefa Shi 《Global Geology》 2006年第1期19-29,共11页
In order to make use of ocean clay reasonably and excavate its potential applications the properties of ocean clay in Chinese investigating area of the East Pacific have been tested with the chemical analysis, XRFS, I... In order to make use of ocean clay reasonably and excavate its potential applications the properties of ocean clay in Chinese investigating area of the East Pacific have been tested with the chemical analysis, XRFS, ICP/MAS, granulometry and SSA, etc. The results show that the clay sediments of this area are rich in clay minerals, fine granularity, bigger SSA, bigger water absorbability and lower ion changing ability etc. To improve the adaptability of ocean clay and macromolecule materials, using the dry milling method with silane, aluminate, stearic acid coupling agents etc the properties of ocean clay are improved. The effect has been evaluated by testing the water absorbing of the modified ocean clay and their dispersing in paraffin liquid. The result is that KH550 is better than any other active reagents, and the best activation technics is that 1.5% (volume) of KH550 quantity, 20min of milling time. The DTA, XRD, SEM and IR analyses and SSA testing show that the organic activation can not change the mineral structure but can densify the structure of clay, and activation mechanism is chemical covered mainly and chemical combined secondly. 展开更多
关键词 ocean clay organic activation structure PROPERTY
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Role of Mass Media in Facilitating Citizen’s Participation in Bangladesh Public Procurement
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作者 Farhana Razzaque 《Cultural and Religious Studies》 2017年第12期691-702,共12页
Public procurement (PP) is considered as one of the key most important functions of any government across the world. Over the years, it has been argued by the scholars that third party engagement (except government... Public procurement (PP) is considered as one of the key most important functions of any government across the world. Over the years, it has been argued by the scholars that third party engagement (except government officials and bidders) in procurement system facilitates to achieve good governance in this sector. In this regard, it is generally expected that third-party monitoring (TPM) of PP, especially monitoring by citizens might earn the trust and confidence of the people in government activities. This study aims at exploring the roles of media in promoting citizen engagement (CE) in PP in order to make the procurement process impartial, efficient, effective, and accountable. The study uses a qualitative methodology in conducting the research with the data being collected through key informant interview, semi-structured interviews, Focus Group Discussions (FGD), secondary document, and literature reviews. The findings of this study suggest that if the media can play an effective role, the procurement literacy rate will be increasing. Hence, an enabling environment could be created where people will feel at ease to talk about compliance with procurement rules and acts. Hence, media may act as a catalyst to promote citizens involvement in the PP process to hold the respective groups accountable for their activities. 展开更多
关键词 PP TPM MEDIA CE
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An integrative study of larval organogenesis of American shad Alosa sapidissima in histological aspects 被引量:1
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作者 高小强 洪磊 +3 位作者 刘志峰 郭正龙 王耀辉 雷霁霖 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第1期136-152,共17页
We describe organogenesis at a histological level in American shad( Alosa sapidissima) larvae from 0 until 45 days after hatching(DAH). Larval development was divided into four stages based on the feeding mode,externa... We describe organogenesis at a histological level in American shad( Alosa sapidissima) larvae from 0 until 45 days after hatching(DAH). Larval development was divided into four stages based on the feeding mode,external morphological features,and structural changes in the organs: stage 1(0–2 DAH),stage 2(3–5 DAH),stage 3(6–26 DAH) and stage 4(27–45 DAH). At early stage 2(3 DAH),American shad larvae developed the initial digestive and absorptive tissues,including the mouth and anal opening,buccopharyngeal cavity,oesophagus,incipient stomach,anterior and posterior intestine,differentiated hepatocytes,and exocrine pancreas. The digestive and absorptive capacity developed further in stages 2 to 3,at which time the pharyngeal teeth,taste buds,gut mucosa folds,differentiated stomach,and gastric glands could be observed. Four defined compartments were discernible in the heart at 4 DAH. From 3 to 13 DAH,the excretory systems started to develop,accompanied by urinary bladder opening,the appearance and development of primordial pronephros,and the proliferation and convolution of renal tubules. Primordial gills were detected at 2 DAH,the pseudobranch was visible at 6 DAH,and the filaments and lamellae proliferated rapidly during stage 3. The primordial swim bladder was first observed at 2 DAH and started to inflate at 9 DAH; from then on,it expanded constantly. The spleen was first observed at 8 DAH and the thymus was evident at 12 DAH. From stage 4 onwards,most organs essentially manifested an increase in size,number,and complexity of tissue structure. 展开更多
关键词 Alosa sapidissima larval development ONTOGENY HISTOLOGY organ differentiation
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Internet Thinking and the Transformation of Traditional Firms
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作者 李海舰 田跃新 李文杰 《China Economist》 2015年第3期114-125,共12页
The Internet and mobile internet have made the transaction of a huge number of products and services possible in ways previously unimaginable, exerting an extensive and profound influence on commercial, industrial, fi... The Internet and mobile internet have made the transaction of a huge number of products and services possible in ways previously unimaginable, exerting an extensive and profound influence on commercial, industrial, financial and even medical enterprises, universities and government agencies. All of this wide variety of transformations can be distilled into the concept of "Internet thinking. " This paper poses that internet thinking consists of the following three levels. First is lnternet spirit, i.e., openness, equality, collaboration and sharing. Second is Internet philosophy, including interconnection between virtual and real entities, elimination of restrictions of time and space, modularization, personal imperialism, crowdsourcing and user-centered approaches. Third is the Internet economy, featuring long-tail theory at a technical level, market equilibrium theory at the level of transaction structure and consumer sovereignty theory at the level of transaction performance. According to Internet thinking, traditional firms must be transformed towards smart organizations characterized by network-based ecosystem, global integration, platform-based operation, users as contributors, borderless development and self- organizing management. As rightly pointed out by the CEO of Haier Group Zhang Ruimin, "There is no such a thing as a successful firm; there are only firms defined by their times. " Adapting to the times is key to the survival of all firms. 展开更多
关键词 Internet era Internet thinking smart organizations
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Charge transfer and orbital reconstruction of non‐noble transition metal single‐atoms anchored on Ti_(2)CT_(x)‐MXenes for highly selective CO_(2) electrochemical reduction 被引量:3
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作者 Neng Li Jiahe Peng +2 位作者 Zuhao Shi Peng Zhang Xin Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第7期1906-1917,共12页
Inspired by MXene nanosheets and their regulation of surface functional groups,a series of Ti_(2)C‐based single‐atom electrocatalysts(TM@Ti_(2)CT_(x),TM=V,Cr,Mn,Fe,Co,and Ni)with two dif‐ferent functional groups(T=... Inspired by MXene nanosheets and their regulation of surface functional groups,a series of Ti_(2)C‐based single‐atom electrocatalysts(TM@Ti_(2)CT_(x),TM=V,Cr,Mn,Fe,Co,and Ni)with two dif‐ferent functional groups(T=–O and–S)was designed.The CO_(2)RR catalytic performance was stud‐ied using well‐defined ab initio calculations.Our results show that the CO_(2) molecule can be more readily activated on TM@Ti_(2)CO_(2) than the TM@Ti_(2)CS_(2) surface.Bader charge analysis reveals that the Ti_(2)CO_(2) substrate is involved in the adsorption reaction,and enough electrons are injected into the 2π*u orbital of CO_(2),leading to a V‐shaped CO_(2) molecular configuration and partial negative charge distribution.The V‐shaped CO_(2) further reduces the difficulty of the first hydrogenation reac‐tion step.The calculatedΔG of the first hydrogenation reaction on TM@Ti_(2)CO_(2) was significantly lower than that of the TM@Ti_(2)CS_(2) counterpart.However,the subsequent CO_(2) reduction pathways show that the UL of the potential determining step on TM@Ti_(2)CS_(2) is smaller than that of TM@Ti_(2)CO_(2).Combining the advantages of both TM@Ti_(2)CS_(2) and TM@Ti_(2)CO_(2),we designed a mixed functional group surface with–O and–S to anchor TM atoms.The results show that Cr atoms an‐chored on the surface of mixed functional groups exhibit high catalytic activity for the selective production of CH4.This study opens an exciting new avenue for the rational design of highly selec‐tive MXene‐based single‐atom CO_(2)RR electrocatalysts. 展开更多
关键词 TM@Ti_(2)CTx MXene Single‐atom catalyst CO_(2)RR Orbital reconstruction Charge transform Mixed functional group surface
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Structure characteristics and adhesive property of humic substances extracted with different methods
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作者 张元波 韩桂洪 +4 位作者 姜涛 黄艳芳 李光辉 郭宇峰 杨永斌 《Journal of Central South University》 SCIE EI CAS 2011年第4期1041-1046,共6页
The structure characteristics and adhesive property of humic substance(HS) extracted with different methods were mainly studied by terms of elementary analysis,visible spectrum,FT-IR spectroscopy,viscosity,adsorption ... The structure characteristics and adhesive property of humic substance(HS) extracted with different methods were mainly studied by terms of elementary analysis,visible spectrum,FT-IR spectroscopy,viscosity,adsorption and pelletizing experiments.The results show that HSs extracted with new method(HS-a) own higher degree of aromatization and polymerization,larger relative molecular mass and more polar functional groups than HS extracted with usual method(HS-b).The viscosity of HS-b is about 30-40 mPa·s lower than that of HS-a.The maximum adsorption amounts of HS-a and HS-b onto iron concentrates are 9.11 mg/g and 8.08 mg/g,respectively.Meanwhile,HS-a has a better performance than HS-b in the practical application for pelletizing of iron concentrates.The difference in agglomeration behaviors with iron concentrates lies in the differences of the structure characteristics of HSs.With higher content of polar functional groups,larger relative molecular mass and viscosity of HSs,the agglomeration behavior is improved. 展开更多
关键词 humic substances structure characteristic agglomeration behaviour green ball
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When Two Sisters Jointly.Ruled an Empire
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作者 Valentine J. Belfiglio 《Sociology Study》 2016年第6期410-416,共7页
This study will examine the ascent of two women as emperors of the Eastern Roman Empire within the context of constructivism and feminist international relations theory. Constructivism emphasizes ideas, such as the co... This study will examine the ascent of two women as emperors of the Eastern Roman Empire within the context of constructivism and feminist international relations theory. Constructivism emphasizes ideas, such as the content of language and social discourse, over institutions or power. Feminism critiques international relations as a male-centered and dominated discipline. This paper addresses important issues. The first issue is a better understanding of the ascent of two women as Chief Executives of a patriarchal system. The second issue is to increase understanding of how gender is constructed and functions in social, cultural, historical, and institutional contexts, particularly as they intersect with political leadership roles. The thesis of this study is that class, political ambition, and political adroitness are more important than gender and social construction in determining the rise of women to high political office. The work implies that women at the higher end of the social stratum have a significant advantage over men and women at the lower end of the social stratum. 展开更多
关键词 CONSTRUCTIVISM FEMINISM class political ambition political adroitness
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Meristem control of leaf patterning 被引量:1
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作者 XU Lin 《Science China(Life Sciences)》 SCIE CAS CSCD 2015年第3期315-316,共2页
Plant organs are derived from stem cells.Once a leaf primordium initiates growth from the shoot apical meristem(SAM),it establishes adaxial-abaxial(dorsal-ventral)polarity.This polarity essentially allows the leaf... Plant organs are derived from stem cells.Once a leaf primordium initiates growth from the shoot apical meristem(SAM),it establishes adaxial-abaxial(dorsal-ventral)polarity.This polarity essentially allows the leaf to become a flat structure with the lamina expanding along the juxtaposition,i.e.,the middle domain,between the adaxial and abaxial domains. 展开更多
关键词 polarity expanding dorsal lamina shoot essentially capturing organs auxin ventral
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3D metal-organic frameworks based on lanthanide-seamed dimeric pyrogallol[4]arene nanocapsules 被引量:2
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作者 Kongzhao Su Mingyan Wu +3 位作者 Wenjing Wang Mi Zhou Daqiang Yuan Maochun Hong 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第6期664-669,共6页
Two novel 3D metal-organic frameworks(MOFs)with cds network,{[Me NH_3]_7[Ln_8(Pg C_2)_2(H_2O)_y(HCOO)_7]}_n·x(Solvent)(FJI-Y4,FJI=Fujian Institute,Ln=Gd,y=12;FJI-Y5,Ln=Dy,y=11;Pg C_2=C-ethylpyrogallol[4]arene),ba... Two novel 3D metal-organic frameworks(MOFs)with cds network,{[Me NH_3]_7[Ln_8(Pg C_2)_2(H_2O)_y(HCOO)_7]}_n·x(Solvent)(FJI-Y4,FJI=Fujian Institute,Ln=Gd,y=12;FJI-Y5,Ln=Dy,y=11;Pg C_2=C-ethylpyrogallol[4]arene),based on unprecedented dimeric pyrogallol[4]arene-based Ln_8metal-organic nanocapsule(MONC)supramolecular building blocks and formate linkers,have been prepared under solvothermal conditions.To our best of knowledge,they present not only the first two examples of 3D hierarchical structures constructed from MONCs in metal-pyrogallol[4]arene system,but also the first two examples of MOFs based on lanthanide MONCs.Remarkably,the inner cavity volume of the Ln_8capsule in FJI-Y4 and FJI-Y5 is approximately151?~3,which is larger than those found in previous transition metal-seamed dimeric Pg C_n-based MONCs.Magnetic investigation on FJI-Y4 suggests a significant magnetocaloric effect(23.97 J kg^(-1)K^(-1),ΔH=7 T,2.5 K),while FJI-Y5 exhibits slow relaxation of the magnetization. 展开更多
关键词 LANTHANIDE arene metal-organic frameworks(MOFs) magnetic propeties
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Enantioselective synthesis of mixed 3,3’-bisindoles via a phosphine-catalyzed umpolung γ-addition of 3’-indolyl-3-oxindoles to allenoates 被引量:1
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作者 Yildiz Tasdan Guang-Jian Mei Yixin Lu 《Science Bulletin》 SCIE EI CAS CSCD 2020年第7期557-563,M0004,共8页
An enantioselective umpolung γ-addition reaction of 3’-indolyl-3-oxindoles to allenoates catalyzed by amino acid-derived bifunctional phosphine catalysts has been developed. A wide range of chiral mixed 3,3’-bisind... An enantioselective umpolung γ-addition reaction of 3’-indolyl-3-oxindoles to allenoates catalyzed by amino acid-derived bifunctional phosphine catalysts has been developed. A wide range of chiral mixed 3,3’-bisindole scaffolds containing an all-carbon quaternary stereogenic center were obtained in high yields and with excellent enantioselectivities. 3,3’-Bisindoles are valuable synthetic intermediates, the employment of which led to formal total syntheses of(+)-Chimonanthine,(+)-Folicanthine and(-)-Calycanthine, as well as facile creation of useful pyrrolidinoindoline core structure. 展开更多
关键词 Umpolung c-addition Amino acid-derived bifunctional phosphine ALLENOATES Mixed 3 30-Bisindole Formal total syntheses
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Highly efficient green organic light-emitting devices based on terbium complex by employing hole block material as host
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作者 ZHAO XueSen ZHAO ZiFeng +5 位作者 ZHOU Liang ZHU Qi LIU ZhiWei BIAN ZuQiang HUANG ChunHui ZHANG HongJie 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2018年第9期1334-1339,共6页
In this work,efficient green electroluminescent(EL)devices with simplified device structure were prepared by doping trivalent terbium complex Tb(PMIP)3into hole block material Tm Py PB.The high triplet energy of T... In this work,efficient green electroluminescent(EL)devices with simplified device structure were prepared by doping trivalent terbium complex Tb(PMIP)3into hole block material Tm Py PB.The high triplet energy of Tm Py PB helps to confine excitons within light-emitting layer,while the electron transport characteristic of Tm Py PB facilitates the balance of carriers on Tb(PMIP)a3molecules.By optimizing the doping concentration of Tb(PMIP)a3and the thickness of each functional layer,highly efficient green EL device with the structure of ITO/Mo Oa3(3 nm)/TAPC(50 nm)/Tb(PMIP)a3(30 wt%):Tm Py PB(25 nm)/Tm Py PB(60 nm)/Li F(1 nm)/Al(100 nm)displayed pure Tb^3+ characteristic emission with maximum current efficiency,power efficiency and brightness up to 47.24 cd/A(external quantum efficiency(EQE)of 14.4%),43.63 lm/W and 1694 cd/m^2,respectively.At certain brightness of 100 cd/m^2,the device still maintained a current efficiency of 19.96 cd/A(EQE=6.1%).Such a device design strategy helps to improve the EL performances of Tb(PMIP)a3and to simplify device fabrication processes,thus reduce the fabrication cost. 展开更多
关键词 ELECTROLUMINESCENCE terbium complex device structure carriers' balance
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