Dharamvir Bharati’s Suraj Ka Satvan Ghoda connects the text with the social reality,through the multiple narrative perspectives of the“Panchatantra”Narrative Structure and the love stories,and narrates the survival...Dharamvir Bharati’s Suraj Ka Satvan Ghoda connects the text with the social reality,through the multiple narrative perspectives of the“Panchatantra”Narrative Structure and the love stories,and narrates the survival and spiritual dilemma of Indian women in the transformation of India’s modernization.The novel depicts in both content and form the plight of Indian women’s physical and spiritual dependence under the traditional concepts of arranged marriages,caste marriages,dowry system and patriarchal will,and shows the process of women’s body and self-consciousness gradually moving from vitality to extinction.展开更多
The sluggish kinetics of the oxygen reduction reaction(ORR)is the bottleneck for various electrochemical energy conversion devices.Regulating the electronic structure of electrocatalysts by ligands has received partic...The sluggish kinetics of the oxygen reduction reaction(ORR)is the bottleneck for various electrochemical energy conversion devices.Regulating the electronic structure of electrocatalysts by ligands has received particular attention in deriving valid ORR electrocatalysts.Here,the surface electronic structure of Ptbased noble metal aerogels(NMAs)was modulated by various organic ligands,among which the electron-withdrawing ligand of 4-methylphenylene effectively boosted the ORR electrocatalysis.Theoretical calculations suggested the smaller energy barrier for the transformation of O^(*) to OH^(*) and downshift the d-band center of Pt due to the interaction between 4-methylphenylene and the surface metals,thus enhancing the ORR intrinsic activity.Both Pt3Ni and Pt Pd aerogels with 4-methylphenylene decoration performed significant enhancement in ORR activity and durability in different media.Remarkably,the 4-methylphenylene modified Pt Pd aerogel exhibited the higher halfwave potential of 0.952 V and the mass activity of 10.2 times of commercial Pt/C.This work explained the effect of electronic structure on ORR electrocatalytic properties and would promote functionalized NMAs as efficient ORR electrocatalysts.展开更多
The developed auxiliary software serves to simplify, standardize and facilitate the software loading of the structural organization of a complex technological system, as well as its further manipulation within the pro...The developed auxiliary software serves to simplify, standardize and facilitate the software loading of the structural organization of a complex technological system, as well as its further manipulation within the process of solving the considered technological system. Its help can be especially useful in the case of a complex structural organization of a technological system with a large number of different functional elements grouped into several technological subsystems. This paper presents the results of its application for a special complex technological system related to the reference steam block for the combined production of heat and electricity.展开更多
Layer-structured Ruddlesden–Popper(RP)perovskites(RPPs)with decent stability have captured the imagination of the photovoltaic research community and bring hope for boosting the development of perovskite solar cell(P...Layer-structured Ruddlesden–Popper(RP)perovskites(RPPs)with decent stability have captured the imagination of the photovoltaic research community and bring hope for boosting the development of perovskite solar cell(PSC)technology.However,two-dimensional(2D)or quasi-2D RP PSCs are encountered with some challenges of the large exciton binding energy,blocked charge transport and poor film quality,which restrict their photovoltaic performance.Fortunately,these issues can be readily resolved by rationally designing spacer cations of RPPs.This review mainly focuses on how to design the molecular structures of organic spacers and aims to endow RPPs with outstanding photovoltaic applications.We firstly elucidated the important roles of organic spacers in impacting crystallization kinetics,charge transporting ability and stability of RPPs.Then we brought three aspects to attention for designing organic spacers.Finally,we presented the specific molecular structure design strategies for organic spacers of RPPs aiming to improve photovoltaic performance of RP PSCs.These proposed strategies in this review will provide new avenues to develop novel organic spacers for RPPs and advance the development of RPP photovoltaic technology for future applications.展开更多
This study explores the impact of organization structure on human resource management in a bi-national organization Tanzania-Zambia Railway Authority (TAZARA). It is a bi-national organization because it is jointly ...This study explores the impact of organization structure on human resource management in a bi-national organization Tanzania-Zambia Railway Authority (TAZARA). It is a bi-national organization because it is jointly owned and managed by the two contacting states of the United Republic of Tanzania and the Republic of Zambia. Tanzania-Zambia Railway stretches 1,860 meters from the Port of Dares Salaam in East Africa to New Kapiri Mposhi in Zambia. The study seeks to provide answers to such questions as what is an organization structure. Can an organization structure affect human resource management in an organization? If so how? What type of organiTation structure can be appropriate for a bi-national organization? What are the advantages and the limitations of the organization structure designed for TAZARA? What measures can be taken to deal with the disadvantages? Organization structure refers to the formal arrangement of tasks, communication, and authority relationships that influence and control how people coordinate and conduct their work (Martin & Fellenz, 2010). The study was undertaken within phenomenological paradigm due to the nature of the inquiry of the impact of the organization structure on a bi-national organization concerned with the relationships of actors such as governments as both institutions and employers and employees as individuals and groups. Phenomenological paradigm is concerned with the understanding of human behavior from the participants' frame of reference. The study was designed as a case study where the researcher explores a phenomenon (case) in this case ( the organization structure) bounded in time and activity (in this case TAZARA as an institution) and collects data using a variety of procedures during a sustained period of time. It was appropriate for exploring, understanding, and obtaining in depth knowledge of understanding the impact of organization structure on a bi-national organization Tanzania-Zambia Railway Authority, which is divided into two regions and the Head office. Both primary and secondary data were collected from the two regions and the Head office. Primary data were collected by focus group discussion, and structured interviews and questionnaires while secondary data were collected by archival method, organization documents, books, and news papers. Data were analyzed using both qualitative and quantitative methods by triangulation techniques. Sample size comprised eight governments and Board of Directors officials, 35 Management officials, 11 trade union officials and 58 focus group members from seven discussions groups, and bring the total to 112. The study revealed that the organization structure has both advantages and limitations. From governments' perspective the structure provides the means of maintaining equal commitment, ownership, and management of the organization by the two contracting states, while the business perspective has identified two limitations. First, the three-tier structure is expensive because of duplication of duties. Second, the involvement of government officials in managing the organization brings in government bureaucracy which should be avoided in business due to slow decision making. Efforts to change the structure to make it business, as so far have proved futile due to governments' reluctance to refinquish power as this will be seen as reducing their commitment to the organization.展开更多
Capital structure is one of the important research aspects of corporate finance. According to methodology, the capital structure research can be classified into two categories: the paradigm of uni-corporation and the...Capital structure is one of the important research aspects of corporate finance. According to methodology, the capital structure research can be classified into two categories: the paradigm of uni-corporation and the paradigm of industry organization. Traditional capital structure research can be attribute to uni-corporation aspect. This paper reviews all literatures concerning the paradigm of industry organization and illustrates the inter-relationship among the feature of industry, the feature of suppliers and customers, the competitive strategy, product life cycle and capital structure.展开更多
Global climate change can affect tree growth and carbon sink function by influencing plant carbohydrate synthesis and utilization,while elevation can be used as an ideal setting under natural conditions to simulate cl...Global climate change can affect tree growth and carbon sink function by influencing plant carbohydrate synthesis and utilization,while elevation can be used as an ideal setting under natural conditions to simulate climate change effects.The effect of elevation on tree growth may depend on organ type.However,the allocation patterns of nonstructural and structural carbohydrates(NSCs and SCs,respectively)in different tree organs and their response to elevation remain unclear.We selected four dominant tree species,Schima superba,Castanopsis eyrei,Castanopsis fargesii and Michelia maudiae,along an elevation gradient from 609 to 1,207 m in subtropical evergreen broad-leaved forests and analyzed leaf,trunk,and fine root NSCs,carbon(C),nitrogen(N)and phosphorus(P)concentrations and the relative abundance of SCs.Leaf NSCs increased initially and then decreased,and trunk NSCs increased with increasing elevation.However,root NSCs decreased with increasing elevation.The relative abundance of SCs in leaves and trunks decreased,while the relative abundance of root SCs increased with increasing elevation.No significant correlations between SCs and NSCs in leaves were detected,while there were negative correlations between SCs and NSCs in trunks,roots,and all organs.Hierarchical partitioning analysis indicated that plant C/N and C/P were the main predictors of changes in SCs and NSCs.Our results suggest that tree organs have divergent responses to elevation and that increasing elevation will inhibit the aboveground part growth and enhance the root growth of trees.A tradeoff between the C distribution used for growth and storage was confirmed along the elevation gradient,which is mainly manifested in the"sink"organs of NSCs.Our results provide insight into tree growth in the context of global climate change scenarios in subtropical forest ecosystems.展开更多
On the basis of questionnaire survey results of 100 agricultural cooperative economic organizations in Three Gorges Reservoir Area,this article uses the structural equation modeling as analysis tool to conduct empiric...On the basis of questionnaire survey results of 100 agricultural cooperative economic organizations in Three Gorges Reservoir Area,this article uses the structural equation modeling as analysis tool to conduct empirical analysis of the governance structure and performance of agricultural cooperative economic organizations. The results show that the ownership structure has the most critical impact on the performance of cooperative organizations,and the impact coefficient is as high as 0.92; the importance of oversight mechanism is basically equivalent to that of the council structure for cooperative organizations,and the impact coefficient is 0.87 and 0.86,respectively,second only to the ownership structure; the size of members' quit capacity also has a very important impact on the performance of organizations,with impact coefficient of 0.74. Thus,the problems influencing the performance of organizations,in the current governance structure of agricultural cooperative economic organizations in Three Gorges Reservoir Area,are pointed out. Finally,corresponding countermeasures are put forward.展开更多
Zeolite synthesis in contemporary chemical industries is predominantly conducted using organic structure‐directing agents(OSDAs),which are chronically hazardous to humans and the environment.It is a growing trend to ...Zeolite synthesis in contemporary chemical industries is predominantly conducted using organic structure‐directing agents(OSDAs),which are chronically hazardous to humans and the environment.It is a growing trend to develop an eco‐friendly and nuisanceless OSDA for zeolite synthesis.Herein,choline is employed as a non‐toxic and green OSDA to synthesize high silica Y zeolite with SiO2/Al2O3 ratios of 6.5–6.8.The prepared Y zeolite samples exhibited outstanding(hydro)thermal stability at ultrahigh temperature owing to the higher SiO2/Al2O3 ratio.The XRF,SEM,29Si‐NMR and 13Na+results suggested that choline plays a structure‐directing role in the synthesis of Y zeolite,while the feed molar fraction of Na+is a crucial determinant for the framework SiO2/Al2O3 ratio and the crystal morphology.展开更多
A novel spherical tremella-like Sb2O3 was prepared by using metal-organic frameworks(MOFs)method under a mild liquid-phase reaction condition,and was further employed as an anode material for lithium-ion batteries(LIB...A novel spherical tremella-like Sb2O3 was prepared by using metal-organic frameworks(MOFs)method under a mild liquid-phase reaction condition,and was further employed as an anode material for lithium-ion batteries(LIBs).The effect of reaction temperature and time on morphologies of Sb2O3 was studied.The results from SEM and TEM demonstrate that the tremella-like Sb2O3 architecture are composed of numerous nanosheets with high specific surface area.When the tremella-like Sb2O3 was used as LIBs anode,the discharge and charge capacities can achieve 724 and 446 mA·h/g in the first cycle,respectively.Moreover,the electrode retains an impressive high capacity of 275 mA·h/g even after 50 cycles at 20 mA/g,indicating that the material is extremely promising for application in LIBs.展开更多
A magnesium metal organic framework, [N-H2(CH3)2][-N(CH3)4][Mgs(bpdc)3(O2CH)6]· 3H2O (1, bpdcH2 = 4,4'-biphenyldicarboxylic acid), has been solvothermally synthesized and structurally characterized. 1 ...A magnesium metal organic framework, [N-H2(CH3)2][-N(CH3)4][Mgs(bpdc)3(O2CH)6]· 3H2O (1, bpdcH2 = 4,4'-biphenyldicarboxylic acid), has been solvothermally synthesized and structurally characterized. 1 crystallizes in the trigonal system, space group R-3, with a = 11.3427(3), c = 41.5662(18) A, V = 4631.3(3) A^3, Z = 3 and the final R = 0.0457. Its structure features a pillared-layered three-dimensional network with 8.21 A cavities, in which cationic [NH2(CH3)2]^+ or [N(CH3)4]^+ and lattice water molecules are located. Thermal stability of the title compound has also been investigated.展开更多
Chemical preparation, X-ray single crystal, thermal analysis and IR spectroscopic investigation of (C7H10N)2 SO4 denoted NMAS are described. The NMAS crystallizes in the triclinic system with P-1 space group. Its unit...Chemical preparation, X-ray single crystal, thermal analysis and IR spectroscopic investigation of (C7H10N)2 SO4 denoted NMAS are described. The NMAS crystallizes in the triclinic system with P-1 space group. Its unit cell dimensions are a = 9.6150(5) ?, b = 9.9744(3) ?, c = 10.2767(6) ?, α = 68.069(3)°, β = 62.929(2)°, γ = 67.285(3)° with V = 785.72(7) ?3 and Z = 2. The structure has been solved using direct method and refined to a reliability R factor of 3.62%. The NMAS structure is built up from chains containing all the components of the structure and parallel to the b axis, linked via N—H-----···O hydrogen bonds. Stability between successive chains is performed by weak interactions originating from the organic cations.展开更多
The desert plant Hedysarum scoparium uses leaflets and rachises as its photosynthetic organs. The abundance of leaflets was lower under unfavorable environmental conditions and higher with improved water conditions. T...The desert plant Hedysarum scoparium uses leaflets and rachises as its photosynthetic organs. The abundance of leaflets was lower under unfavorable environmental conditions and higher with improved water conditions. To examine the characteristics associated with the adaptation of H. scoparium to its environment, we selected plants with both compound leaves and rachis without leaflets to study the anatomical structures and gas exchange characteristics of the two organs. The results show that the water storage tissues in rachises were more developed compared with the leaflets. The diurnal courses of the net photosynthetic rate for the rachis and the leaflet were both in a bimodal pattern. Meanwhile, both two peak values of the rachis were significantly higher than those of the leaflet. The daily average transpiration rate was significantly higher in the rachis than in the leaflet in order to lower the temperature of the rachises. It was concluded that under desert drought conditions, the leaflets of H. scoparium were partially or completely degraded to reduce the transpiration area as an adaptive response to water deficit, and only the rachises were retained as photosynthetic organ. The rachises were found to be better suited to a desert habitat than the leaflets.展开更多
Kerogen plays an important role in shale gas adsorption,desorption and diffusion.Therefore,it is necessary to characterize the molecular structure of kerogen.In this study,four kerogen samples were isolated from the o...Kerogen plays an important role in shale gas adsorption,desorption and diffusion.Therefore,it is necessary to characterize the molecular structure of kerogen.In this study,four kerogen samples were isolated from the organic-rich shale of the Longmaxi Formation.Raman spectroscopy was used to determine the maturity of these kerogen samples.Highresolution transmission electron microscopy(HRTEM),13 C nuclear magnetic resonance(13 C NMR),X-ray diffraction(XRD)and Fourier transform infrared(FT-IR)spectroscopy were conducted to characterize the molecular structure of the shale samples.The results demonstrate that VReqv of these kerogen samples vary from 2.3%to 2.8%,suggesting that all the kerogen samples are in the dry gas window.The macromolecular carbon skeleton of the Longmaxi Formation kerogen is mainly aromatic(fa’=0.56).In addition,the aromatic structural units are mainly composed of naphthalene(23%),anthracene(23%)and phenanthrene(29%).However,the aliphatic structure of the kerogen macromolecules is relatively low(fal*+falH=0.08),which is presumed to be distributed in the form of methyl and short aliphatic chains at the edge of the aromatic units.The oxygen-containing functional groups in the macromolecules are mainly present in the form of carbonyl groups(fac=0.23)and hydroxyl groups or ether groups(falO=0.13).The crystallite structural parameters of kerogen,including the stacking height(Lc=22.84?),average lateral size(La=29.29?)and interlayer spacing(d002=3.43?),are close to the aromatic structural parameters of anthracite or overmature kerogen.High-resolution transmission electron microscopy reveals that the aromatic structure is well oriented,and more than 65%of the diffractive aromatic layers are concentrated in the main direction.Due to the continuous deep burial,the longer aliphatic chains and oxygen-containing functional groups in the kerogen are substantially depleted.However,the ductility and stacking degree of the aromatic structure increases during thermal evolution.This study provides quantitative information on the molecular structure of kerogen samples based on multiple research methods,which may contribute to an improved understanding of the organic pores in black shale.展开更多
The reaction of MeCpLnCl·2LiCl·nTHF with 2 equivalent of LiNPh_2 in THF,hexane and toluene mixture solution gives the new complex[Li(DME)_2][(η~5-MeCp)Ln(NPh_2)_3](Ln=La,Pr,Nd)by extraction with DME.They ha...The reaction of MeCpLnCl·2LiCl·nTHF with 2 equivalent of LiNPh_2 in THF,hexane and toluene mixture solution gives the new complex[Li(DME)_2][(η~5-MeCp)Ln(NPh_2)_3](Ln=La,Pr,Nd)by extraction with DME.They have been characterized by elemental analysis,IR and NMR.The La complex crystallizes in the monoclinic space group P2_1/c with α=1.8335(6)nm,b=1.6576(5)nm,c=1.7461(6)nm, β=96.04°,V=5.277 nm^2,Z=4,D_c=1.26g·cm^(-3),R=0.057 and R_w=0.048(1≥2.5σ(I_o))for 3378 reflec- tions.The complex consists of a pair of a cation and an anion.La^(3+) is coordinated by one methylcyclopentadienyl and three diphenylamidos to form six-coordinate pseudotetrahedron with the mean Ln-N and La-C(ring)distances of 0.2459(8)and 0.2843(11)nm,respectively.展开更多
One novel metal-organic framework(MOF), [Ba(L)(HO)](1, HL =aniline-2,5-disulfonic acid), has been synthesized by hydrothermal method. Each barium atom is eleven-coordinated into a distorted monocapped pentagonal antip...One novel metal-organic framework(MOF), [Ba(L)(HO)](1, HL =aniline-2,5-disulfonic acid), has been synthesized by hydrothermal method. Each barium atom is eleven-coordinated into a distorted monocapped pentagonal antiprismatic arrangement. Compound 1 shows an interesting 3 D pillar-layered structure constructed from 2 D inorganic layers[Ba(SO)(HO)]and organic pillars of phenyl moieties of L2-linkages. The inorganic layers are supported by the organic pillars, generating a novel 3 D open framework structure with {3, 4~6, 5~5, 6~5,7~4}2{3}{5} topology. The result of fluorescence measurement can reveal that the decayed emission band centered at 492 nm may be caused by the interactions of the ligands and the metal ions.Compound 1 exhibits selective toward the adsorption of COover Nat 273 K.展开更多
By the reactions of manganese(if) acetate, 2-sulfoethylphosphonic acid, 1,10-phen (1,10-phen = 1, 10-phenanthroline) or cobalt(Ⅱ) acetate, 4,4'-bipy and 2-carboxyethylphosphonic acid, two novel compounds of [M...By the reactions of manganese(if) acetate, 2-sulfoethylphosphonic acid, 1,10-phen (1,10-phen = 1, 10-phenanthroline) or cobalt(Ⅱ) acetate, 4,4'-bipy and 2-carboxyethylphosphonic acid, two novel compounds of [Mn(H2O)2(C12H8N2) (HO3PCH2CH2CO2) ] (1) and[Co(H2O)4(C10H8N2)]-(HOaPCH2CH2CO2) (2) have been synthesized and characterized by IR spectroscopy, elemental analyses and single-crystal X-ray diffraction. Compound 1 has a 0D structure. Two Mn(ii) ions are linked by two 2-carboxyethylphosphonic acid ligands, forming a centrosymmetric dimer. These dimers are further interlinked into a 2D layer structure by π-π stacking interactions and hydrogen bonds. Compound 2 has a 1D chain structure. The 2-carboxyethylphosphonic acid remains uncoordinated and acts as the organic template. By the bridge of 4,4'-bipy, the [Co(4,4'-bipy)]^2+ chains are formed.展开更多
The crystal structure of the title compound (C17H19Cl2N2O3P, Mr = 401.21) has been determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 6.1648(6), b = 19.943(2), c...The crystal structure of the title compound (C17H19Cl2N2O3P, Mr = 401.21) has been determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 6.1648(6), b = 19.943(2), c = 15.268(2) ?, β = 99.220(2)°, V = 1852.8(3) ?3, Z = 4, Dc = 1.438 g/cm3, F(000) = 832, μ(MoKα) = 0.456 mm-1, the final R = 0.0622 and wR = 0.1586 for 3986 observed reflections (I > 2σ(I)). X-ray analysis reveals that the product is a thermodynamically stable cis isomer. The intramolecular hydrogen bond N(2)–H(2A)…O(1) is observed in the title compound.展开更多
The organic salt, (H2Bpy)(cda)2, was synthesized by the reaction of sodium car- bamyldicyanomethanide, 4,4-bipyridyl and manganese(II) perchlorate in water solution. The crystal belongs to monoclinic, space group C2/c...The organic salt, (H2Bpy)(cda)2, was synthesized by the reaction of sodium car- bamyldicyanomethanide, 4,4-bipyridyl and manganese(II) perchlorate in water solution. The crystal belongs to monoclinic, space group C2/c with a = 20.333(7), b = 6.177(2), c = 15.566(5) ? b = 116.860(5), V = 1744(1) ?, Z = 4, C18H14N8O2 (Mr = 374.37), Dc = 1.426 g/cm3, F(000) = 776, m = 0.100 mm-1 and l = 0.71073 ? The structure was refined to R = 0.0560 and wR = 0.1072 for 590 observed reflections (I > 2s(I)). Two nitrogen atoms of the 4,4?bipyridyl molecule bonded to two hydrogen ions, resulting this neutral molecule into a divalent cation. Through the interaction of colorless H2bpy cation and colorless cda anion the red neutral organic salt was formed.展开更多
文摘Dharamvir Bharati’s Suraj Ka Satvan Ghoda connects the text with the social reality,through the multiple narrative perspectives of the“Panchatantra”Narrative Structure and the love stories,and narrates the survival and spiritual dilemma of Indian women in the transformation of India’s modernization.The novel depicts in both content and form the plight of Indian women’s physical and spiritual dependence under the traditional concepts of arranged marriages,caste marriages,dowry system and patriarchal will,and shows the process of women’s body and self-consciousness gradually moving from vitality to extinction.
基金supported by the National Natural Science Foundation of China(22374119,21902128)the China Postdoctoral Science Foundation(2021M692620)+1 种基金the Research Fund of the State Key Laboratory of Solidification Processing(NPU),China(2021-QZ-01)the Key Project of Natural Science Fund of Shaanxi Province(2023-JC-ZD-06)。
文摘The sluggish kinetics of the oxygen reduction reaction(ORR)is the bottleneck for various electrochemical energy conversion devices.Regulating the electronic structure of electrocatalysts by ligands has received particular attention in deriving valid ORR electrocatalysts.Here,the surface electronic structure of Ptbased noble metal aerogels(NMAs)was modulated by various organic ligands,among which the electron-withdrawing ligand of 4-methylphenylene effectively boosted the ORR electrocatalysis.Theoretical calculations suggested the smaller energy barrier for the transformation of O^(*) to OH^(*) and downshift the d-band center of Pt due to the interaction between 4-methylphenylene and the surface metals,thus enhancing the ORR intrinsic activity.Both Pt3Ni and Pt Pd aerogels with 4-methylphenylene decoration performed significant enhancement in ORR activity and durability in different media.Remarkably,the 4-methylphenylene modified Pt Pd aerogel exhibited the higher halfwave potential of 0.952 V and the mass activity of 10.2 times of commercial Pt/C.This work explained the effect of electronic structure on ORR electrocatalytic properties and would promote functionalized NMAs as efficient ORR electrocatalysts.
文摘The developed auxiliary software serves to simplify, standardize and facilitate the software loading of the structural organization of a complex technological system, as well as its further manipulation within the process of solving the considered technological system. Its help can be especially useful in the case of a complex structural organization of a technological system with a large number of different functional elements grouped into several technological subsystems. This paper presents the results of its application for a special complex technological system related to the reference steam block for the combined production of heat and electricity.
基金funding from National Science Foundation of China(52202337 and 22178015)the Young Taishan Scholars Program of Shandong Province(tsqn202211082)+1 种基金Natural Science Foundation of Shandong Province(ZR2023MB051)Independent Innovation Research Project of China University of Petroleum(East China)(22CX06023A).
文摘Layer-structured Ruddlesden–Popper(RP)perovskites(RPPs)with decent stability have captured the imagination of the photovoltaic research community and bring hope for boosting the development of perovskite solar cell(PSC)technology.However,two-dimensional(2D)or quasi-2D RP PSCs are encountered with some challenges of the large exciton binding energy,blocked charge transport and poor film quality,which restrict their photovoltaic performance.Fortunately,these issues can be readily resolved by rationally designing spacer cations of RPPs.This review mainly focuses on how to design the molecular structures of organic spacers and aims to endow RPPs with outstanding photovoltaic applications.We firstly elucidated the important roles of organic spacers in impacting crystallization kinetics,charge transporting ability and stability of RPPs.Then we brought three aspects to attention for designing organic spacers.Finally,we presented the specific molecular structure design strategies for organic spacers of RPPs aiming to improve photovoltaic performance of RP PSCs.These proposed strategies in this review will provide new avenues to develop novel organic spacers for RPPs and advance the development of RPP photovoltaic technology for future applications.
文摘This study explores the impact of organization structure on human resource management in a bi-national organization Tanzania-Zambia Railway Authority (TAZARA). It is a bi-national organization because it is jointly owned and managed by the two contacting states of the United Republic of Tanzania and the Republic of Zambia. Tanzania-Zambia Railway stretches 1,860 meters from the Port of Dares Salaam in East Africa to New Kapiri Mposhi in Zambia. The study seeks to provide answers to such questions as what is an organization structure. Can an organization structure affect human resource management in an organization? If so how? What type of organiTation structure can be appropriate for a bi-national organization? What are the advantages and the limitations of the organization structure designed for TAZARA? What measures can be taken to deal with the disadvantages? Organization structure refers to the formal arrangement of tasks, communication, and authority relationships that influence and control how people coordinate and conduct their work (Martin & Fellenz, 2010). The study was undertaken within phenomenological paradigm due to the nature of the inquiry of the impact of the organization structure on a bi-national organization concerned with the relationships of actors such as governments as both institutions and employers and employees as individuals and groups. Phenomenological paradigm is concerned with the understanding of human behavior from the participants' frame of reference. The study was designed as a case study where the researcher explores a phenomenon (case) in this case ( the organization structure) bounded in time and activity (in this case TAZARA as an institution) and collects data using a variety of procedures during a sustained period of time. It was appropriate for exploring, understanding, and obtaining in depth knowledge of understanding the impact of organization structure on a bi-national organization Tanzania-Zambia Railway Authority, which is divided into two regions and the Head office. Both primary and secondary data were collected from the two regions and the Head office. Primary data were collected by focus group discussion, and structured interviews and questionnaires while secondary data were collected by archival method, organization documents, books, and news papers. Data were analyzed using both qualitative and quantitative methods by triangulation techniques. Sample size comprised eight governments and Board of Directors officials, 35 Management officials, 11 trade union officials and 58 focus group members from seven discussions groups, and bring the total to 112. The study revealed that the organization structure has both advantages and limitations. From governments' perspective the structure provides the means of maintaining equal commitment, ownership, and management of the organization by the two contracting states, while the business perspective has identified two limitations. First, the three-tier structure is expensive because of duplication of duties. Second, the involvement of government officials in managing the organization brings in government bureaucracy which should be avoided in business due to slow decision making. Efforts to change the structure to make it business, as so far have proved futile due to governments' reluctance to refinquish power as this will be seen as reducing their commitment to the organization.
文摘Capital structure is one of the important research aspects of corporate finance. According to methodology, the capital structure research can be classified into two categories: the paradigm of uni-corporation and the paradigm of industry organization. Traditional capital structure research can be attribute to uni-corporation aspect. This paper reviews all literatures concerning the paradigm of industry organization and illustrates the inter-relationship among the feature of industry, the feature of suppliers and customers, the competitive strategy, product life cycle and capital structure.
基金the National Natural Science Foundation of China(32260379&32371852)the Jiangxi Provincial Natural Science Foundation(20224ACB215005)
文摘Global climate change can affect tree growth and carbon sink function by influencing plant carbohydrate synthesis and utilization,while elevation can be used as an ideal setting under natural conditions to simulate climate change effects.The effect of elevation on tree growth may depend on organ type.However,the allocation patterns of nonstructural and structural carbohydrates(NSCs and SCs,respectively)in different tree organs and their response to elevation remain unclear.We selected four dominant tree species,Schima superba,Castanopsis eyrei,Castanopsis fargesii and Michelia maudiae,along an elevation gradient from 609 to 1,207 m in subtropical evergreen broad-leaved forests and analyzed leaf,trunk,and fine root NSCs,carbon(C),nitrogen(N)and phosphorus(P)concentrations and the relative abundance of SCs.Leaf NSCs increased initially and then decreased,and trunk NSCs increased with increasing elevation.However,root NSCs decreased with increasing elevation.The relative abundance of SCs in leaves and trunks decreased,while the relative abundance of root SCs increased with increasing elevation.No significant correlations between SCs and NSCs in leaves were detected,while there were negative correlations between SCs and NSCs in trunks,roots,and all organs.Hierarchical partitioning analysis indicated that plant C/N and C/P were the main predictors of changes in SCs and NSCs.Our results suggest that tree organs have divergent responses to elevation and that increasing elevation will inhibit the aboveground part growth and enhance the root growth of trees.A tradeoff between the C distribution used for growth and storage was confirmed along the elevation gradient,which is mainly manifested in the"sink"organs of NSCs.Our results provide insight into tree growth in the context of global climate change scenarios in subtropical forest ecosystems.
文摘On the basis of questionnaire survey results of 100 agricultural cooperative economic organizations in Three Gorges Reservoir Area,this article uses the structural equation modeling as analysis tool to conduct empirical analysis of the governance structure and performance of agricultural cooperative economic organizations. The results show that the ownership structure has the most critical impact on the performance of cooperative organizations,and the impact coefficient is as high as 0.92; the importance of oversight mechanism is basically equivalent to that of the council structure for cooperative organizations,and the impact coefficient is 0.87 and 0.86,respectively,second only to the ownership structure; the size of members' quit capacity also has a very important impact on the performance of organizations,with impact coefficient of 0.74. Thus,the problems influencing the performance of organizations,in the current governance structure of agricultural cooperative economic organizations in Three Gorges Reservoir Area,are pointed out. Finally,corresponding countermeasures are put forward.
基金supported by the National Natural Science Foundation of China(Grant No.21802136)~~
文摘Zeolite synthesis in contemporary chemical industries is predominantly conducted using organic structure‐directing agents(OSDAs),which are chronically hazardous to humans and the environment.It is a growing trend to develop an eco‐friendly and nuisanceless OSDA for zeolite synthesis.Herein,choline is employed as a non‐toxic and green OSDA to synthesize high silica Y zeolite with SiO2/Al2O3 ratios of 6.5–6.8.The prepared Y zeolite samples exhibited outstanding(hydro)thermal stability at ultrahigh temperature owing to the higher SiO2/Al2O3 ratio.The XRF,SEM,29Si‐NMR and 13Na+results suggested that choline plays a structure‐directing role in the synthesis of Y zeolite,while the feed molar fraction of Na+is a crucial determinant for the framework SiO2/Al2O3 ratio and the crystal morphology.
基金Project(51674114)supported by the National Natural Science Foundation of ChinaProject(2019JJ40069)supported by the Natural Science Foundation of Hunan Province,ChinaProject(16K025)supported by the Key Laboratory of the Education Department of Hunan Province,China
文摘A novel spherical tremella-like Sb2O3 was prepared by using metal-organic frameworks(MOFs)method under a mild liquid-phase reaction condition,and was further employed as an anode material for lithium-ion batteries(LIBs).The effect of reaction temperature and time on morphologies of Sb2O3 was studied.The results from SEM and TEM demonstrate that the tremella-like Sb2O3 architecture are composed of numerous nanosheets with high specific surface area.When the tremella-like Sb2O3 was used as LIBs anode,the discharge and charge capacities can achieve 724 and 446 mA·h/g in the first cycle,respectively.Moreover,the electrode retains an impressive high capacity of 275 mA·h/g even after 50 cycles at 20 mA/g,indicating that the material is extremely promising for application in LIBs.
基金supported by the NNSFC (No. 20873149)the Knowledge Innovation Program of the Chinese Academy of Sciences (KJCX2-XW-H21)
文摘A magnesium metal organic framework, [N-H2(CH3)2][-N(CH3)4][Mgs(bpdc)3(O2CH)6]· 3H2O (1, bpdcH2 = 4,4'-biphenyldicarboxylic acid), has been solvothermally synthesized and structurally characterized. 1 crystallizes in the trigonal system, space group R-3, with a = 11.3427(3), c = 41.5662(18) A, V = 4631.3(3) A^3, Z = 3 and the final R = 0.0457. Its structure features a pillared-layered three-dimensional network with 8.21 A cavities, in which cationic [NH2(CH3)2]^+ or [N(CH3)4]^+ and lattice water molecules are located. Thermal stability of the title compound has also been investigated.
文摘Chemical preparation, X-ray single crystal, thermal analysis and IR spectroscopic investigation of (C7H10N)2 SO4 denoted NMAS are described. The NMAS crystallizes in the triclinic system with P-1 space group. Its unit cell dimensions are a = 9.6150(5) ?, b = 9.9744(3) ?, c = 10.2767(6) ?, α = 68.069(3)°, β = 62.929(2)°, γ = 67.285(3)° with V = 785.72(7) ?3 and Z = 2. The structure has been solved using direct method and refined to a reliability R factor of 3.62%. The NMAS structure is built up from chains containing all the components of the structure and parallel to the b axis, linked via N—H-----···O hydrogen bonds. Stability between successive chains is performed by weak interactions originating from the organic cations.
基金supported by the National Natu-ral Sciences Foundation of China (40771005 30870382)+1 种基金the CAS (Chinese Academy of Sciences) Action Plan for West Development Project (KZCX2-XB2-04-01KZCX2-XB2-09-03)
文摘The desert plant Hedysarum scoparium uses leaflets and rachises as its photosynthetic organs. The abundance of leaflets was lower under unfavorable environmental conditions and higher with improved water conditions. To examine the characteristics associated with the adaptation of H. scoparium to its environment, we selected plants with both compound leaves and rachis without leaflets to study the anatomical structures and gas exchange characteristics of the two organs. The results show that the water storage tissues in rachises were more developed compared with the leaflets. The diurnal courses of the net photosynthetic rate for the rachis and the leaflet were both in a bimodal pattern. Meanwhile, both two peak values of the rachis were significantly higher than those of the leaflet. The daily average transpiration rate was significantly higher in the rachis than in the leaflet in order to lower the temperature of the rachises. It was concluded that under desert drought conditions, the leaflets of H. scoparium were partially or completely degraded to reduce the transpiration area as an adaptive response to water deficit, and only the rachises were retained as photosynthetic organ. The rachises were found to be better suited to a desert habitat than the leaflets.
基金supported by the National Science and Technology Major Project(2017ZX05035004–002)the National Natural Science Foundation of China(no.41702167)+1 种基金the Fundamental Research Funds for the Central Universities(No.2017CXNL03)the Scientific Research Foundation of the Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process,Ministry of Education(China University of Mining and Technology)(No.2017–007)
文摘Kerogen plays an important role in shale gas adsorption,desorption and diffusion.Therefore,it is necessary to characterize the molecular structure of kerogen.In this study,four kerogen samples were isolated from the organic-rich shale of the Longmaxi Formation.Raman spectroscopy was used to determine the maturity of these kerogen samples.Highresolution transmission electron microscopy(HRTEM),13 C nuclear magnetic resonance(13 C NMR),X-ray diffraction(XRD)and Fourier transform infrared(FT-IR)spectroscopy were conducted to characterize the molecular structure of the shale samples.The results demonstrate that VReqv of these kerogen samples vary from 2.3%to 2.8%,suggesting that all the kerogen samples are in the dry gas window.The macromolecular carbon skeleton of the Longmaxi Formation kerogen is mainly aromatic(fa’=0.56).In addition,the aromatic structural units are mainly composed of naphthalene(23%),anthracene(23%)and phenanthrene(29%).However,the aliphatic structure of the kerogen macromolecules is relatively low(fal*+falH=0.08),which is presumed to be distributed in the form of methyl and short aliphatic chains at the edge of the aromatic units.The oxygen-containing functional groups in the macromolecules are mainly present in the form of carbonyl groups(fac=0.23)and hydroxyl groups or ether groups(falO=0.13).The crystallite structural parameters of kerogen,including the stacking height(Lc=22.84?),average lateral size(La=29.29?)and interlayer spacing(d002=3.43?),are close to the aromatic structural parameters of anthracite or overmature kerogen.High-resolution transmission electron microscopy reveals that the aromatic structure is well oriented,and more than 65%of the diffractive aromatic layers are concentrated in the main direction.Due to the continuous deep burial,the longer aliphatic chains and oxygen-containing functional groups in the kerogen are substantially depleted.However,the ductility and stacking degree of the aromatic structure increases during thermal evolution.This study provides quantitative information on the molecular structure of kerogen samples based on multiple research methods,which may contribute to an improved understanding of the organic pores in black shale.
文摘The reaction of MeCpLnCl·2LiCl·nTHF with 2 equivalent of LiNPh_2 in THF,hexane and toluene mixture solution gives the new complex[Li(DME)_2][(η~5-MeCp)Ln(NPh_2)_3](Ln=La,Pr,Nd)by extraction with DME.They have been characterized by elemental analysis,IR and NMR.The La complex crystallizes in the monoclinic space group P2_1/c with α=1.8335(6)nm,b=1.6576(5)nm,c=1.7461(6)nm, β=96.04°,V=5.277 nm^2,Z=4,D_c=1.26g·cm^(-3),R=0.057 and R_w=0.048(1≥2.5σ(I_o))for 3378 reflec- tions.The complex consists of a pair of a cation and an anion.La^(3+) is coordinated by one methylcyclopentadienyl and three diphenylamidos to form six-coordinate pseudotetrahedron with the mean Ln-N and La-C(ring)distances of 0.2459(8)and 0.2843(11)nm,respectively.
基金supported by the Liaoning Provincial Education Department(No.L2015299)Innovative training program for College Students(Nos.201710148000118,201710148000147)
文摘One novel metal-organic framework(MOF), [Ba(L)(HO)](1, HL =aniline-2,5-disulfonic acid), has been synthesized by hydrothermal method. Each barium atom is eleven-coordinated into a distorted monocapped pentagonal antiprismatic arrangement. Compound 1 shows an interesting 3 D pillar-layered structure constructed from 2 D inorganic layers[Ba(SO)(HO)]and organic pillars of phenyl moieties of L2-linkages. The inorganic layers are supported by the organic pillars, generating a novel 3 D open framework structure with {3, 4~6, 5~5, 6~5,7~4}2{3}{5} topology. The result of fluorescence measurement can reveal that the decayed emission band centered at 492 nm may be caused by the interactions of the ligands and the metal ions.Compound 1 exhibits selective toward the adsorption of COover Nat 273 K.
基金supported by the Natural Science Foundation for Youths in Jiangxi Province (No. 2008GQH0002)
文摘By the reactions of manganese(if) acetate, 2-sulfoethylphosphonic acid, 1,10-phen (1,10-phen = 1, 10-phenanthroline) or cobalt(Ⅱ) acetate, 4,4'-bipy and 2-carboxyethylphosphonic acid, two novel compounds of [Mn(H2O)2(C12H8N2) (HO3PCH2CH2CO2) ] (1) and[Co(H2O)4(C10H8N2)]-(HOaPCH2CH2CO2) (2) have been synthesized and characterized by IR spectroscopy, elemental analyses and single-crystal X-ray diffraction. Compound 1 has a 0D structure. Two Mn(ii) ions are linked by two 2-carboxyethylphosphonic acid ligands, forming a centrosymmetric dimer. These dimers are further interlinked into a 2D layer structure by π-π stacking interactions and hydrogen bonds. Compound 2 has a 1D chain structure. The 2-carboxyethylphosphonic acid remains uncoordinated and acts as the organic template. By the bridge of 4,4'-bipy, the [Co(4,4'-bipy)]^2+ chains are formed.
文摘The crystal structure of the title compound (C17H19Cl2N2O3P, Mr = 401.21) has been determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 6.1648(6), b = 19.943(2), c = 15.268(2) ?, β = 99.220(2)°, V = 1852.8(3) ?3, Z = 4, Dc = 1.438 g/cm3, F(000) = 832, μ(MoKα) = 0.456 mm-1, the final R = 0.0622 and wR = 0.1586 for 3986 observed reflections (I > 2σ(I)). X-ray analysis reveals that the product is a thermodynamically stable cis isomer. The intramolecular hydrogen bond N(2)–H(2A)…O(1) is observed in the title compound.
基金This work was supported by the National Natural Science Foundation of China (20271043) and the Natural Science Foundation of Shandong province(y2002B10)
文摘The organic salt, (H2Bpy)(cda)2, was synthesized by the reaction of sodium car- bamyldicyanomethanide, 4,4-bipyridyl and manganese(II) perchlorate in water solution. The crystal belongs to monoclinic, space group C2/c with a = 20.333(7), b = 6.177(2), c = 15.566(5) ? b = 116.860(5), V = 1744(1) ?, Z = 4, C18H14N8O2 (Mr = 374.37), Dc = 1.426 g/cm3, F(000) = 776, m = 0.100 mm-1 and l = 0.71073 ? The structure was refined to R = 0.0560 and wR = 0.1072 for 590 observed reflections (I > 2s(I)). Two nitrogen atoms of the 4,4?bipyridyl molecule bonded to two hydrogen ions, resulting this neutral molecule into a divalent cation. Through the interaction of colorless H2bpy cation and colorless cda anion the red neutral organic salt was formed.