Fluorine substitution position effects on spiro(fluorene-9,9’-xanthene) cored hole transporting materials for high-performance planar perovskite solar cells

Fluorine substitution in molecular design has become an effective strategy for improving the overall performance of organic photovoltaics.In this study,three low-cost small molecules of spiro-linked hole transporting materials(SFX-O-2 F,SFX-m-2 F,and SFX-p-2 F) endowed with two-armed t rip he ny la mine moieties were synthesized via tuning of the fluorine substitution position,and they were employed for use in highly efficient perovskite solar cells(PSCs).Despite the fluorine substitution position playing a negligible role in the optical and electrochemical properties of the resulting small molecules,the photovoltaic performance thereof was observed to vary significantly.The planar n-i-p PSCs based on SFX-m-2 F demonstrated superior performance(18.86%) when compared to that of the corresponding SFX-o-2 F(9.7%) and SFX-p-2 F(16.33%) under 100 mW cm^(-2) AM1.5 G solar illumination,which is competitive with the performance of the benchmark spiro-OMeTAD-based device(18.98%).Moreover,the SFX-m-2 Fbased PSCs were observed to be more stable than the spiro-OMeTAD-based devices under ambient conditions.The improved performance of SFX-m-2 F is primarily associated with improved morphology,more efficient hole transport,and extraction characteristics at the perovskite/HTM interface.This work demonstrated the application of fluorination engineering to the tuning of material film morphology and charge transfer properties,showing the promising potential of fluorinated SM-HTMs for the construction of low-cost,high-efficiency PSCs.

Enhancing wood efficiency through comprehensive wood flow analysis:Methodology and strategic insights

Wood,an essential natural resource in human civilization,remains widely used despite advances in technology and material substitution.The surge in greenhouse gas emissions and environmental concerns accentuates the need for optimizing wood utilization.Material flow analysis is a powerful tool for tracking material flows and stocks,aiding resource management and environmental decision-making.However,the full extent of its methodological dimensions,particularly within the context of the wood supply chain,remains relatively unexplored.In this study,we delve into the existing literature on wood flow analysis,discussing its primary objectives,materials involved,temporal and spatial scales,data sources,units,and conversion factors.Additionally,data uncertainty,data reconciliation and crucial assumptions in material flow analysis are highlighted in this paper.Key findings reveal the significance of wood cascading and substitution effects by replacing non-wood materials,where they can reduce greenhouse gas emissions more than the natural carbon sink of forests and wood products.The immediate impact of short-term wood cascading might not be as robust as the substitution effect,with energy substitution showcasing better results than material substitution.However,it's crucial to note that these conclusions could experience significant reversal from a long-term and global perspective.Strategies for improving wood efficiency involve maximizing material use,advancing construction technologies,extending product lifespans,promoting cascade use,and optimizing energy recovery processes.The study underscores the need for standardized approaches in wood flow analysis and emphasizes the potential of wood efficiency strategies in addressing environmental challenges.

Off-farm employment,agriculture production activities,and household dietary diversity in environmentally and economically vulnerable areas of Asia

Access to off-farm employment has been expected to be a critical approach to ending hunger and all forms of malnutrition,two important targets of achieving Zero Hunger.This study aims to investigate the role of off-farm employment in improving dietary diversity through substitution effect and complementary effect with agricultural production activities and income effect.This study adopts Poisson/Tobit/Probit/OLS regressions and the instrument variable method based on the primary survey data collected among 1,282 households at 12 sites in environmentally and economically vulnerable areas of China,Nepal,Cambodia,Thailand,and Myanmar in 2019.The results show that off-farm employment is positively associated with household dietary diversity and the consumption of flesh meat,fish and other aquatic animals,fruits,and milk and dairy products,which are rich in protein and micronutrients.The results of mechanism analysis show that off-farm employment contributes to household dietary diversity by improving crop diversity,especially for poor households,boosting the probability of livestock raising for households with the middle one-third disposal income,and increasing household income.The positive association between off-farm employment and household dietary diversity is much higher for households with the bottom one-third disposal income,low illiteracy,and from upper-middle income countries.These findings imply that off-farm employment does play a vital role in achieving multiple benefits of poverty alleviation,malnutrition reduction,and agrobiodiversity conservation in environmentally and economically vulnerable areas.However,it may enlarge the gaps in dietary diversity between households with low human capital and from low and lower-middle income countries and those with high human capital and from middle-high countries.

The Lead-Chelating Effects of Substituted Dithiocarbamates

The effectiveness of certain substituted dithiocarbamates in mobilizing lead from preexposed rats was investigated.The animals received 10mg Pb/kg/day, intragastrically.for 8 weeks and were treated thereafter with 400μmol/kg, intraperitoneally.of morpholine dithiocarbamate, tetraammonium ethylenediamine diacetic acid dithiocarbamate (EDDTC), ammonium diethanolamine dithiocarbamate (ADDTC), sodium diethyldithiocarbamate.N-benzyl-D-glucamine dithiocarbamate (NBGDTC), or dimercaptosuccinic acid, daily for 5 days.All the chelating agents were effective in lowering the hepatic and renal burden of Pb.ADDTC.EDDTC, and NBGDTC were also able to lower the long bone Pb content.The lowering of Pb burden had no relationship to restoration of Pb-induced hematopoietic alterations.The relatively lower lipophilicity of substituted dithiocarbamates, owing to the presence of hydrophilic groups, seems to be advantageous in preventing passage of metal chelale into the brain.None of the substituted dithiocarbamates caused excessive excretion of urinary Cu and Zn.ADDTC and EDDTC appear to be promising in the management of Pb poisoning. 1990 Academic Press.Inc.

Effect of the Partial Substitution of V for Nb on the Magnetic Properties of Fe-based Nanocrystalline Alloy

The variation of the magnetic properties of the nanocrystalline alloys for the partial substitution of V for Nb with crystallizing treatment temperature and time was investigated. The variation law of the magnetic properties with the annealing temperature and time is essentially the same. The magnetic properties of the Fe-based nanocrystalline alloys for the partial substitution of V for Nb reduce, and the crystallizing treatment temperature of the alloys increases. The optimum properties of Fe74Cu1Nb3Si13B9 nanocrystalline alloys crystallized at 550℃x60 min are μ0=9.2xl0^4, μm=54.8xl0^4, Hc=1.14 A/m and Bs=1.26 T. The best properties for Fe74Cu1Nb3Si13B9 alloys annealed at 560℃x60 min are μ0=8.79x10^4, μm=50.18xl0^4, Hc=1.26 A/m and Bs=1.24 T.

Effect of Zn Substitution on Magnetic Properties of CuFe_2O_4： a High-Temperature Series Expansions Study

The magnetic properties of spinel ferrites Cu_（1-x）Zn_xFe_2O_4 are studied using high-temperature series expansions combined with the Padé approximates. The exchange interactions, inter and intra-sublattices J_（AA）, J_（BB） and J_（AB） are obtained using a probability distribution law. The critical exponent associated with the magnetic susceptibility is obtained.

药品集中带量采购对抗菌药物使用的影响分析:以阿莫西林为例

目的分析抗菌药物集中带量采购(以下简称“集采”)后使用变化,为完善我国带量采购政策和促进合理用药提供参考。方法采用描述性统计分析和间断时间序列分析方法,将第二批和第三批药品集采政策落地时间设为政策干预点,分析2019年1月—2021年12月全国医药企业阿莫西林销售量和销售金额在集采前后的变化情况。结果阿莫西林胶囊剂和颗粒剂在集采后销售量大幅上升,非中选的胶囊剂和颗粒剂销售量也有所上升,但涨幅低于市场整体增长率。非集采剂型中的阿莫西林片剂和混悬剂销售量和销售金额均出现降低,口服剂型中选能有效降低同为口服剂型的其他非集采品规销售量,阿莫西林注射剂销售量和销售金额在集采后短期内明显增长,通过模型预测阿莫西林注射剂长期的销售量和销售金额呈下降趋势。结论药品带量采购能够实现药价降低且达成以量换价的目标,中选药品使用量显著增长,但需要关注同通用名下非集采剂型的使用量情况,减少不同剂型间替代使用的情况;应该进一步扩大抗菌药物集采范围,将更多临床具体替代关系的药物纳入采购范畴,加强对临床抗菌药物的使用监测,保障临床抗菌药物合理使用。

Theoretical Investigations of Nonlinear Optical Properties of Transition Metal Cluster Anions

In the framework of density functional theory （DFT）, the electronic excitations and nonlinear optical （NLO） properties of six binuclear transition metal cluster anions with the formula of [Ch2M-（μ-Ch）2-M＇CN]^2- （M = Mo, W; Ch = S, Se; M＇ = Cu, Ag） have been systemically investigated at both cases of gas phase and DMF solution. The obtained electronic absorption spectra reveal that the element replacements of metals M and ligands Ch have significant influence on the absorptions, especially on the low-lying ones. In addition, the transitions of μ-Ch→M are dominant for the low-lying excitations, whereas the transitions of M＇→M as well as Ch→M are mainly responsible for the higher excitations. The calculated molecular first and second hyperpolarizabilities present the remarkable element substitution and solvent effects. The analyses show that the transitions involving μ-Ch→M charge transfer make the critical contributions to the first hyperpolarizability t, and that the charge transfers from the moieties of MCh4 to M＇CN as well as those of μ-Ch→M and M＇→M are responsible for the second hyperpolarizability y. Moreover, the introduction of solvent leads to the results that the transitions within the moieties of MCh4 and M＇CN make larger contributions to the hyperpolarizability, especially to γ.

Experimental and genomic evidence for the indica-type cytoplasmic effect in Oryza sativa L.ssp.japonica

Cytoplasmic effects are important agronomical phenomena that have generated widespread interest in both theory and application. In the present study, five high yield rice cultivars（Oryza sativa L. ssp. japonica） in large-scale cultivation in northeast China were determined to possess Oryza sativa L. ssp. indica-type cytoplasm using cytoplasmic subspecies-specific molecular markers. This was confirmed by cytoplasmic genome-wide single nucleotide polymorphisms（SNPs） and functional gene sequencing. Two of these five japonica cultivars were core breeding parents with high yield and the other three were super-high-yield varieties registered by the Ministry of Agriculture of China. We constructed nuclear substitution lines to further demonstrate whether and how this indica-type cytoplasm contributed to yield improvement by comparing yield components. The results showed that under the same japonica nuclear background, the lines with indica-type cytoplasm had a significant decrease in tillers in exchange for increased grain number per panicle compared with their recurrent parents. Our results implied that botanical basis of this cytoplasmic effect was to reduce the plant＇s branching differentiation to produce more floral organs under the constant nutrition. Our findings open another door for the utilization of inter-subspecific hybridization for the improvement of rice cultivar.

Robot Application and Labor Force Employment:Substitution or Complementation?——An Empirical Analysis Based on the Data from 22 Economies

The rise of robotics has brought great uncertainty to the labor market.Based on the sectoral data from 22 economies during 2008-2019,this paper explores the impact of robot application on employment.The results show that,on the whole,robot application will have complementary effects on labor force employment,and the grouped regression by economic development level and demographic characteristics supports this conclusion,while the effect of robot application on labor force employment is significantly different by industry.Further research shows that the degree of robot use is the key factor that determines the effect of robots on employment,and the complementary effect is dominant in economies with low degree of robot application,and the subtitution effect is dominant in economies with high degree of robot application.In addition,obvious spillover effects are observed in robotic application.On the one hand,robot application will have a forward crowdingout effect and a reverse siphon effect,which drive the labor force moving from the primary industry to the secondary and tertiary industries.On the other hand,robot application will also have heterogeneous effects on the labor force employment of economies in the upstream and downstream position along the value chain through the transmission effect of the Global Value Chains(GVC).The conclusions of this paper provide some practical implications for the rational formulation of artificial intelligence plans in the context of“stabilizing employment”.

Effect of Co substitution on the glass forming ability and magnetocaloric effect of Fe88Zr8B4 amorphous alloys

As greater attention is paid to energy consumption and global warming,magnetic refrigeration(MR)technologies based on the magneto-caloric effect(MCE)have been developed.Systems based on MR are expected to be more compact。

DEGREE OF BRANCHING OF THE HYPERBRANCHED POLYMERS RESULTED FROM AB_2 POLYCONDENSATION WITH SUBSTITUTION EFFECT

The analytical expressions of the various structural units and the average degree of branching for the hyperbranched polymers resulted from AB2 polycondensation with substitution effect were derived by the kinetic mechanism. The reactivity difference between the 13 group in linear unit and that in terminal group has great effect on the molecular parameters of the products obtained. The concentration of terminal units has a maximum with the increase of the conversion of A groups （x）. The higher the reactivity ratio （r） of linear B group to branched one is, the later the maximum appears and the larger it is. The degree of branching of the hyperbranched polymers obtained is controllable by adjusting the parameters of r and x, which increases with increasing both x and r.

The research on the substitution effect between the wireless and fixed telecommunication industry

Wireless telecommunication has developed at a rapid pace than the fixed telecommunication since the last decades of twentieth century. This article analyzes the effect wireless mobile telecom substitutes for the fixed telecom by employing the normal theory of substitution and econometrics model. The analytical results are consistent with the reality, and it has been observed that the relation between the wireless and fixed telecommunication industry has changed from state of being complementary in the early last decades of twentieth century to that of being substituted at present. Moreover, the enhanced progress of telecommunication technology especially in wireless areas enriches customers＇ demands in terms of multimedia contents thereby changing their communication style, which significantly promotes the rapid growth of wireless mobile communication and strengthens the effect of the substitute.

Theoretical studies on the substitution effect of fluorine on ethylene

The substitution effect of fluorine on ethylene is investigated by means of studying the properties of the charge distribution at the bond critical points with the theory of atoms in molecules.It is found that fluorine atom acts not only as a σ electron acceptor,but also as a π electron donor,and these double effects are reflected in the quantity of ellipticity,Lap- lacian and the charge density of charge distribution at the bond critical points.For C—C,C—F bonds,the major axis of elliptical contours is perpendicular to the molecular plane,but for C—H bond,it is parallel to the molecular plane.Other effects originating from the substi- tution have also been discussed.

A 4-aminonaphthalimide based environmentally sensitive fluorescence probe

A simply synthesized 4-aminonaphthalimide derivative 1 expresses both polarity and viscosity sensitive fluorescence spectra,indicating its potential usage as an environmentally sensitive fluorescence probe. By comparing the fluorescence behavior of 1 with that of a known 4-aminonaphthalimide derivative 2,it was found that the substitution of the 4-amino group has profound influence on the environmentally sensitive fluorescence properties of 4-aminonaphthalimide.

Does Chinese OFDI really promote export?

Does Chinese outward foreign direct investment really promote export?Most papers have come to positive conclusions.Upon reviewing these papers,this paper contributes by correcting model misspecification,wrong variable selection and estimation methods which are prevalent in existing studies,and reexamines the relationship using panel data from 2003 to 2014.The results indicate that:on average,the point estimate of the elasticity between Chinese outward foreign direct investment and export trade is at most 0.073,and it’s not statistically significant.Sub-sample regressions show that,Chinese investment in developed economies slightly substitutes export while investment in developing economies complements export.But these effects disappear when country specific effects are controlled.Year-by-year regressions show that,the complementary effect of OFDI on export is on a steady rise.But if we take the regression coefficients and the quantitative difference between OFDI and export into consideration,the effect is indeed negligible.

Preparation, Structure and Magnetic Properties of Lithium Substituted NiO by Molten Salt Method

A typical Li＋ substituted NiO compound, Li0.29Ni0.710, was synthesized by molten nitrate method. The ef- fects of Li＋ substitution on the structure and magnetic properties of NiO were investigated. X-Ray diffraction（XRD）, scanning electron microscope（SEM） and high-resolution transmission electron microscope（HRTEM） analyses con- firm the cubic structure of Li0.29Ni0,710, with a primary particle size of 150 nm. Analysis of the Ni X-ray photoelec- tron spectroscopy（XPS） shows the transformation from Ni2. to Ni3＋ induced by Li＋ substitution. Two magnetic tran- sitions were observed at 225 and 55 K which were assigned to the ferrimagnetic ordering and spin glass transition, respectively. The different magnetic behavior with respect to that of NiO was attributed to the break of superexchange interaction Ni2＋-O-Ni2＋ and the formation of different spin clusters after non-magnetic Li＋ doping.