Leguminosae plants play a key role in affecting soil physical-chemical and biological properties during grassland succession after farmland abandonment in the Loess Plateau,China

Leguminosae are an important part of terrestrial ecosystems and play a key role in promoting soil nutrient cycling and improving soil properties.However,plant composition and species diversity change rapidly during the process of succession,the effect of leguminosae on soil physical-chemical and biological properties is still unclear.This study investigated the changes in the composition of plant community,vegetation characteristics,soil physical-chemical properties,and soil biological properties on five former farmlands in China,which had been abandoned for 0,5,10,18,and 30 a.Results showed that,with successional time,plant community developed from annual plants to perennial plants,the importance of Leguminosae and Asteraceae significantly increased and decreased,respectively,and the importance of grass increased and then decreased,having a maximum value after 5 a of abandonment.Plant diversity indices increased with successional time,and vegetation coverage and above-and below-ground biomass increased significantly with successional time after 5 a of abandonment.Compared with farmland,30 a of abandonment significantly increased soil nutrient content,but total and available phosphorus decreased with successional time.Changes in plant community composition and vegetation characteristics not only change soil properties and improve soil physical-chemical properties,but also regulate soil biological activity,thus affecting soil nutrient cycling.Among these,Leguminosae have the greatest influence on soil properties,and their importance values and community composition are significantly correlated with soil properties.Therefore,this research provides more scientific guidance for selecting plant species to stabilize soil ecosystem of farmland to grassland in the Loess Plateau,China.

Synergy of inside doped metals–Outside coated graphene to enhance hydrogen storage in magnesium-based alloys

Grain growth of magnesium(Mg)and its hydride is one of the main reasons for kinetic and capacity degradation during the hydrogen absorption and desorption cycles.To solve this problem,herein we propose a novel method involving synergistic effect of inside embedded metals and outside coated graphene to limit the growth of Mg and its hydride grains.The graphene coated Mg-Y-Al alloys were selected as a model system for demonstrating this positive effect where the Mg_(91)Y_(3)Al_(6)alloy was first prepared by rapidly solidified method and then high-pressure milled with 5 wt%graphene upon 5 MPa hydrogen gas for obtaining in-situ formed YAl_(2)and YH_(3)embedded in the MgH_(2)matrix with graphene shell(denoted as MgH_(2)-Y-Al@GR).In comparison to pure MgH_(2),the obtained MgH_(2)-Y-Al@GR composites deliver much better kinetics and more stable cyclic performance.For instance,the MgH_(2)-Y-Al@GR can release about 6.1 wt%H_(2)within 30 min at 300℃ but pure MgH_(2)only desorbs∼1.5 wt%H_(2).The activation energy for desorption of MgH_(2)-Y-Al@GR samples is calculated to be 75.3±9.1 kJ/mol that is much lower than approximately 160 kJ/mol for pure MgH_(2).Moreover,its capacity retention is promoted from∼57%of pure MgH_(2)to∼84%after 50th cycles without obvious particle agglomeration and grain growth.The synergistic effect of outside graphene coating with inside embedded metals which could provide a huge number of active sites for catalysis as well as inhibit the grain growth of Mg and its hydride is believed to be responsible for these.

Tuning synergy between nickel and iron in Ruddlesden-Popper perovskites through controllable crystal dimensionalities towards enhanced oxygenevolving activity and stability

Ni-Fe-based oxides are among the most promising catalysts developed to date for the bottleneck oxygen evolution reaction(OER)in water electrolysis.However,understanding and mastering the synergy of Ni and Fe remain challenging.Herein,we report that the synergy between Ni and Fe can be tailored by crystal dimensionality of Ni,Fe-contained Ruddlesden-Popper(RP)-type perovskites(La_(0.125)Sr_(0.875))n+1(Ni_(0.25)Fe_(0.75))nO3n+1(n=1,2,3),where the material with n=3 shows the best OER performance in alkaline media.Soft X-ray absorption spectroscopy spectra before and after OER reveal that the material with n=3 shows enhanced Ni/Fe-O covalency to boost the electron transfer as compared to those with n=1 and n=2.Further experimental investigations demonstrate that the Fe ion is the active site and the Ni ion is the stable site in this system,where such unique synergy reaches the optimum at n=3.Besides,as n increases,the proportion of unstable rock-salt layers accordingly decreases and the leaching of ions(especially Sr^(2+))into the electrolyte is suppressed,which induces a decrease in the leaching of active Fe ions,ultimately leading to enhanced stability.This work provides a new avenue for rational catalyst design through the dimensional strategy.

Tailoring the microenvironment of Ti sites in Ti-containing materials for synergizing with Au sites to boost propylene epoxidation

Au sites supported on Ti-containing materials(Au/Ti-containing catalyst)are currently considered as a promising catalyst for the propylene epoxidation owing to the synergistic effect that hydrogen peroxide species formed on Au sites diffuses to the Ti sites to form the Ti-hydroperoxo intermedi-ates and contributes to the formation of propylene oxide(PO).In principle,thermal treatment will significantly affect the chemical and physical structures of Ti-containing materials.Consequently,the synergy between tailored Ti sites with different surface properties and Au sites is highly ex-pected to enhance the catalytic performance for the reaction.Herein,we systematically studied the intrinsic effects of different microenvironments around Ti sites on the PO adsorption/desorption and conversion,and then effectively improved the catalytic performance by tailoring the number of surface hydroxyl groups.The Ti^(Ⅵ)material with fewer hydroxyls stimulates a remarkable enhance-ment in PO selectivity and H_(2)efficiency compared to the Ti^(Ⅵ)material that possessed more hydrox-yls,offering a 7-fold and 4-fold increase,respectively.As expected,the Ti^(Ⅵ)+Ⅳand Ti^(Ⅳ)materials also exhibit a similar phenomenon to the Ti^(Ⅵ)materials through the same thermal treatment,which strongly supports that the Ti sites microenvironment is an important factor in suppressing PO con-version and enhancing catalytic performance.These insights could provide guidance for the rational preparation and optimization of Ti-containing materials synergizing with Au catalysts for propylene epoxidation.

Trade-offs and synergies between ecosystem services in Yutian County along the Keriya River Basin,Northwest China

The Keriya River Basin is located in an extremely arid climate zone on the southern edge of the Tarim Basin of Northwest China,exhibiting typical mountain-oasis-desert distribution characteristics.In recent decades,climate change and human activities have exerted significant impacts on the service functions of watershed ecosystems.However,the trade-offs and synergies between ecosystem services(ESs)have not been thoroughly examined.This study aims to reveal the spatiotemporal changes in ESs within the Keriya River Basin from 1995 to 2020 as well as the trade-offs and synergies between ESs.Leveraging the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)and Revised Wind Erosion Equation(RWEQ)using land use/land cover(LULC),climate,vegetation,soil,and hydrological data,we quantified the spatiotemporal changes in the five principal ESs(carbon storage,water yield,food production,wind and sand prevention,and habitat quality)of the watershed from 1995 to 2020.Spearman correlation coefficients were used to analyze the trade-offs and synergies between ES pairs.The findings reveal that water yield,carbon storage,and habitat quality exhibited relatively high levels in the upstream,while food production and wind and sand prevention dominated the midstream and downstream,respectively.Furthermore,carbon storage,food production,wind and sand prevention,and habitat quality demonstrated an increase at the watershed scale while water yield exhibited a decline from 1995 to 2020.Specifically,carbon storage,wind and sand prevention,and habitat quality presented an upward trend in the upstream but downward trend in the midstream and downstream.Food production in the midstream showed a continuously increasing trend during the study period.Trade-off relationships were identified between water yield and wind and sand prevention,water yield and carbon storage,food production and water yield,and habitat quality and wind and sand prevention.Prominent temporal and spatial synergistic relationships were observed between different ESs,notably between carbon storage and habitat quality,carbon storage and food production,food production and wind and sand prevention,and food production and habitat quality.Water resources emerged as a decisive factor for the sustainable development of the basin,thus highlighting the intricate trade-offs and synergies between water yield and the other four services,particularly the relationship with food production,which warrants further attention.This research is of great significance for the protection and sustainable development of river basins in arid areas.

Trade-Offs and Synergie Effects of Regulating Ecosystem Services along an Climatic Gradient in Slovakia

This study aims to assess the synergies and trade-offs of regulating ecosystem services. Ecosystem services are non-linearly interconnected and changes in one service can positively or negatively affect another. We evaluated ecosystem services based on biophysical indicators using an expert scoring system that determines the corresponding soil functions and is part of the existing databases available in Slovakia. This methodological combination enabled us to provide unique mapping and assessment of ecosystem services within Slovakia. Correlation analysis between individual regulating ecosystem services and climate regions, slope, texture, and altitude confirm the statistically significant influence of climate and slope in all agricultural land, arable land, and grassland ecosystems. Statistically significant synergistic effects were established between the regulation of the water regime and the regulation of soil erosion within each climate region, apart from the very warm climate region. Only in a very warm climate region was potential of regulating ecosystem services mutually beneficial for soil erosion control and soil cleaning potential (immobilization of inorganic pollutants).

医科达Synergy医用电子直线加速器故障维修六例

放射治疗是利用放射线治疗肿瘤的医疗方式[1]。医用电子直线加速器作为医院开展放射治疗的重要医疗设备,在肿瘤治疗中发挥重要作用。同时,医用电子直线加速器的技术结构复杂,组成模块、系统、零部件多,集成度高,设备具有“唯一性”、故障风险大等特点,如出现故障不能及时解决,可影响患者治疗效果,严重时甚至会造成不可逆性的重大损伤[2]。目前,医科达Synergy医用电子直线加速器的市场占有率较高,其通信模块较多、运动结构相对复杂,故障率较高。本研究以我院在用的医科达Synergy医用电子直线加速器为例,对其结构原理及6例故障维修过程进行总结分析,以供同行借鉴和参考。

Spatiotemporal variations in ecosystem services and their trade-offs and synergies against the background of the gully control and land consolidation project on the Loess Plateau,China

Studying the spatiotemporal variations in ecosystem services and their interrelationships on the Loess Plateau against the background of the gully control and land consolidation(GCLC)project has significant implications for ecological protection and quality development of the Yellow River Basin.Therefore,in this study,we took Yan'an City,Shaanxi Province of China,as the study area,selected four typical ecosystem services,including soil conservation service,water yield service,carbon storage service,and habitat quality service,and quantitatively evaluated the spatiotemporal variation characteristics and trade-offs and synergies of ecosystem services from 2010 to 2018 using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.We also analysed the relationship between the GCLC project and regional ecosystem service changes in various regions(including 1 city,2 districts,and 10 counties)of Yan'an City and proposed a coordinated development strategy between the GCLC project and the ecological environment.The results showed that,from 2010 to 2018,soil conservation service decreased by 7.76%,while the other three ecosystem services changed relatively little,with water yield service increasing by 0.56% and carbon storage service and habitat quality service decreasing by 0.16% and 0.14%,respectively.The ecological environment of Yan'an City developed in a balanced way between 2010 and 2018,and the four ecosystem services showed synergistic relationships,among which the synergistic relationships between soil conservation service and water yield service and between carbon storage service and habitat quality service were significant.The GCLC project had a negative impact on the ecosystem services of Yan'an City,and the impact on carbon storage service was more significant.This study provides a theoretical basis for the scientific evaluation of the ecological benefits of the GCLC project and the realization of a win-win situation between food security and ecological security.

Responses of microbial activities and soil physical-chemical properties to the successional process of biological soil crusts in the Gurbantunggut Desert,Xinjiang

Biological soil crusts （BSCs） are capable of modifying nutrient availability to favor the establishment of biogeochemical cycles. Microbial activities serve as critical roles for both carbon and nutrient transformation in BSCs. However, little is known about microbial activities and physical-chemical properties of BSCs in the Gurbantunggut Desert, Xinjiang, China. In the present research, a sampling line with 1-m wide and 20-m long was set up in each of five typical interdune areas selected randomly in the Gurbantunggut Desert. Within each sampling line, samples of bare sand sheet, algal crusts, lichen crusts and moss crusts were randomly collected at the depth of 0-2 cm. Varia- tions of microalgal biomass, microbial biomass, enzyme activities and soil physical-chemical properties in different succession of BSCs were analyzed. The relationships between microalgal biomass, microbial biomass, enzymatic activities and soil physical-chemical properties were explored by stepwise regression. Our results indicate that micro- algal biomass, microbial biomass and most of enzyme activities increased as the BSCs developed and their highest values occurred in lichen or moss crusts. Except for total K, the contents of most soil nutrients （organic C, total N, total P, available N, available P and available K） were the lowest in the bare sand sheet and significantly increased with the BSCs development, reaching their highest values in moss crusts. However, pH values significantly decreased as the BSCs developed. Significant and positive correlations were observed between chlorophyll a and microbial biomass C. Total P and N were positively associated with chlorophyll a and microbial biomass C, whereas there was a significant and negative correlation between microbial biomass and available P. The growth of cyanobacteria and microorganism contributed C and N in the soil, which offered substrates for enzyme activities thus increasing enzyme activities. Probably, improvement in enzyme activities increased soil fertility and promoted the growth of cyanobacteria, eukary- otic algae and heterotrophic microorganism, with the accelerating succession of BSCs. The present research found that microalgal-microbial biomass and enzyme activities played important roles on the contents of nutrients in the successional stages of BSCs and helped us to understand developmental mechanism in the succession of BSCs.

Contribution to Comparative Study of Physical-Chemical Characteristics of Diack Basalt and Bandia Limestone for Use in Railway Engineering

This paper presents a comparative study of Physical-Chemical characteristics of Limestone and Basalt (from Senegalese quarries). First, chemical tests show that Basalt is richer in silica 51.59% versus 2.84% for Limestone. Basalt is made up of silica minerals and essentially carbonated minerals with a CaO percentage of 50.05%. Chemical results also show that Basalt is richer in iron 12.71% versus 0.44% for Limestone. Finally, they revealed a fire loss of 40.91% for Limestone and 2.44% for Basalt. Second, physical analysis results show that Diack Basalt has the best characteristics with a flattening coefficient of 5% between 5% and 20%;the percentage of pollutants is 0.36% less than 1%;the Los Angeles coefficient is 12.21% below 15, while Bandia Limestone gives a flattening coefficient of 3%;the Los Angeles coefficient of 40.17% and the percentage of pollutant (2.4%) well above 2%. It is noted that the percentage of Limestone pollutant is too high. These important results show the net advantage of Basalt compared to Limestone in terms of physical-chemical characteristics.

Long-range electron synergy over Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst in enhancing charge separation for photocatalytic hydrogen production

The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.Herein,we fabricate Pt and Co single-atom sites successively on polymeric carbon nitride(CN).In this Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst,the noble-metal active sites are maximized,and the single-atomic Co_(1)N_4sites are tuned to Co_(1)N_3sites by photogenerated electrons arising from the introduced single-atomic Pt_(1)N_4sites.Mechanism studies and density functional theory(DFT)calculations reveal that the 3d orbitals of Co_(1)N_3single sites are filled with unpaired d-electrons,which lead to the improved visible-light response,carrier separation and charge migration for CN photocatalysts.Thereafter,the protons adsorption and activation are promoted.Taking this advantage of long-range electron synergy in bimetallic single atomic sites,the photocatalytic hydrogen evolution activity over Pt_(1)-Co_(1)/CN achieves 915.8 mmol g^(-1)Pt h^(-1),which is 19.8 times higher than Co_(1)/CN and 3.5 times higher to Pt_(1)/CN.While this electron-synergistic effect is not so efficient for Pt nanoclusters.These results demonstrate the synergistic effect at electron-level and provide electron-level guidance for the design of efficient photocatalysts.

QSPR between Physical-Chemical Properties and Molecule Parameters of Alkanes

A set of molecule parameters, namely, N, N′, p, q, n, were used to express the structures of alkanes. A correlative model was established between certain physical-chemical properties and molecular parameters of alkanes by regression method. Eight physical-chemical properties, such as evaporation heat （△vHm^20）, density（D^20 ）, capacity （C^20）, surface tension （δ^20）, boiling point （Tb）, critical temperature（Tc）, critical pressure（Pc） and critical volume（Vc）, of fifty-six C3-C16 alkanes were calculated directly from the model in this paper. The calculated values are in good accordance with the literature ones reported for alkanes, and the correlation coefficients （R） equal or exceed 0.99 . The research results indicate that the principle of the method is simple and clear, the method is practical, the correlativity is excellent, and the predicted data are credible.

Trade-off and Synergy of Rural Functions Under County Depopulation in the Typical Black Soil Region of Northeast China

As the population continues to shrink in the black soil region of Northeast China since 2000,it is critical to master the impact of population shrinkage on rural functions to realize rural revitalization and sustainable development.In this study,we focused on the impacts of depopulation on the evolution and interrelationship of rural subfunctions.Based on the rural function indexes system,the TOPSIS(Technique for Order Preference by Similarity to an Ideal Solution)method,spatial analysis method,and mathematical statistics analysis method were used to summarize the spatial and temporal characteristics of rural function development,as well as the effect of population shrinkage in the typical black soil region of Northeast China.The results showed that depopulation varied in the extent and duration between the forested region and plain areas,which both impacted the trajectories of rural subfunctions evolution.For the economic development function and ecological conservation function,the effect of continuous slight depopulation was beneficial,while the effect of rapid depopulation was adverse,which was exactly opposite to the agricultural production function.All forms of population shrinkage were conducive to the development of the social security function.With the deepening population shrinkage,depopulation mainly promoted the collaborative development between subfunctions in this study,except the relationship between agricultural production and social security function.But effects of depopulation on the interrelationship of rural subfunctions varied between the forested region and plain areas in some cases.The results provided evidence for the cognition that population shrinkage had complicated effects on rural subfunctions.

Variation of soil physical-chemical characteristics in salt-affected soil in the Qarhan Salt Lake,Qaidam Basin

Soil salinization has adverse effects on the soil physical-chemical characteristics.However,little is known about the changes in soil salt ion concentrations and other soil physical-chemical characteristics within the Qarhan Salt Lake and at different soil depths in the surrounding areas.Here,we selected five sampling sites(S1,S2,S3,S4,and S5)alongside the Qarhan Salt Lake and in the Xidatan segment of the Kunlun Mountains to investigate the relationship among soil salt ion concentrations,soil physical-chemical characteristics,and environmental variables in April 2019.The results indicated that most sites had strongly saline and very strongly saline conditions.The main salt ions present in the soil were Na^(+),K^(+),and Cl^(-).Soil nutrients and soil microbial biomass(SMB)were significantly affected by the salinity(P<0.05).Moreover,soil salt ions(Na^(+),K^(+),Ca2+,Mg^(2+),Cl^(-),CO_(3)^(2-),SO_(4)^(2-),and HCO_(3)^(-))were positively correlated with electrical conductivity(EC)and soil water content(SWC),but negatively related to altitude and soil depth.Unlike soil salt ions,soil nutrients and SMB were positively correlated with altitude,but negatively related to EC and SWC.Moreover,soil nutrients and SMB were negatively correlated with soil salt ions.In conclusion,soil nutrients and SMB were mainly influenced by salinity,and were related to altitude,soil depth,and SWC in the areas from the Qarhan Salt Lake to the Xidatan segment.These results imply that the soil quality(mainly evaluated by soil physical-chemical characteristics)is mainly influenced by soil salt ions in the areas surrounding the Qarhan Salt Lake.Our results provide an accurate prediction of how the soil salt ions,soil nutrients,and SMB respond to the changes along a salt gradient.The underlying mechanisms controlling the soil salt ion distribution,soil nutrients,and SMB in an extremely arid desert climate playa should be studied in greater detail in the future.

Physical-Chemical Aggressiveness of Solutions of Medicines as a Factor in the Rheology of the Blood inside Veins and Catheters

In experiments in vitro and observations in the clinic in vivo studied the state of the lumen of subcutaneous veins and blood rheology of patients after their interaction with vascular catheters and solutions of medicines based on the values of temperature, volume, concentration, osmotic activity and pH. It is shown that heparin injection in blood not prevent, but solution of 4% sodium bicarbonate injection prevents blood clotting, blood clots and blockage blood clots of veins and of catheters. It is shown that the heating to a temperature of＋42 ℃ with the solution of 4% sodium bicarbonate provides softening action on old dry blood clots in 1 min, and their subsequent irrigation with a warm solution of 4% sodium bicarbonate and 3% hydrogen peroxide provides complete destruction and discoloration of the remaining spots of blood during 2 s. Proposed new medicines and hygiene products for the protection of the veins and installed in them vascular catheters from blockage of blood clots, and for removing blood stains from clothes and body surface patients.

Compatible stability study of Xing NaoJing injection based on physical-chemical properties analysis

Objective:The clinical treatment of brain diseases is urgent. Xingnaojing (XNJ) injection is often used in combination with other injection drugs. Due to the possible interaction between the injections in vivo, the particle size, osmotic pressure, pH value change and component stability decrease, that is one of the important factors causing various adverse reactions. Based on the above situation, this study investigated the physical properties and chemical composition changes of XNJ injection and its compatibility solvent and 13 kinds of clinical injection, speculated the possible interactions between the drugs in vivo from the perspective of in vitro compatibility stability, find out the safety risks of adverse reactions and provide guidance for the safe and rational use of XNJ injection. Methods:According to the clinical application, XNJ injection was mixed with 13 combination injections based on 250 mL 5% glucose injection, and placed at room temperature for 6 h. Then, the clarity, particle size, pH, osmolality, and the contents of camphor, d-borneol, and muscone of the compatible solutions were detected at 0, 1, 2, 4, and 6 h, respectively. Results:The results showed that the physical-chemical properties of compatibility solution were slightly influenced when XNJ was combined with Alprostadil injection and Danhong injection. The change of particle size and the degradation of muscone content were the main factors affecting the compatibility stability of XNJ injection, indicating that there are some problems in compatibility stability, which may be one of the causes of clinical adverse reactions. Conclusion:This study suggests that XNJ injection in combination with other injections during intravenous administration should be performed cautiously.

Regulating the synergy coefficient of composite materials for alleviating self-discharge of supercapacitors

Supercapacitor is an efficient energy storage device,yet its wider application is still limited by self-discharge.Currently,various composite materials have been reported to have improved inhibition on self-discharge,while the evaluation of the synergistic effect in composite materials is challenging.Herein,pairs of intercalation type pseudocapacitive niobium oxides are pre-lithiated and coupled to construct conjugatedly configured supercapacitors,within which the cathode and anode experience identical reaction environment with single type of charge carrier,thus providing ideal platform to quantify the synergistic effect of composite materials on the self-discharge process.By using titanium dioxide as the stabilizer,we have compared how the modes of forming composite would influence the selfdischarge performance of the active composite materials with similar ratio of the constituent materials.Specifically,core@shell Nb_(2)O_(5)@TiO_(2) composite using TiO_(2) as the shell shows significantly higher synergy coefficient(μ=0.61,defined as the value that evaluates the synergistic effect between composite materials,and can be quantified using the overall performance of the composite,performance of individual component as well as the ratio of the component.) than other control group samples,which corresponds to the highest retained energy of 63% at 100 h.This work is expected to provide a general method for quantifying the synergistic effect and guide the design of composite materials with specific mode of forming the composite.

Recycling Spent LiCoO_(2)Battery as a High-efficient Lithiumdoped Graphitic Carbon Nitride/Co_(3)O_(4)Composite Photocatalyst and Its Synergistic Photocatalytic Mechanism

The ever-increasing quantity of spent lithium-ion batteries(LIBs)is both a potential environmental pollutant and a valuable resource.The spent LIBs recycling mainly aimed at the separation of valuable elements.Some issues still exist in these processes such as high energy consumption and complex separation procedures.This study avoided element separation and proposed a facile approach to transform spent LiCoO_(2) electrode into a lithium(Li)-doped graphitic carbon nitride(g-C_(3)N_(4))/Co_(3)O_(4) composite photocatalyst through one-pot in situ thermal reduction.During the thermal process,melamine served as the reductant for LiCoO_(2) decomposition and the raw material for g-C_(3)N_(4) production.Li was in situ doped in g-C_(3)N_(4) and the generated Co_(3)O_(4) was in situ integrated,forming a Li-doped g-C_(3)N_(4)/Co_(3)O_(4) composite photocatalyst.This special composite exhibited an enhanced photocatalytic performance,and its photocatalytic H2 production and RhB degradation rates were 8.7 and 6.8 times higher than those of g-C_(3)N_(4).The experiments combined with DFT calculation revealed that such enhanced photocatalytic efficiency was ascribed to the synergy effect of Li doping and Co_(3)O_(4) integrating,which extended the visible light absorption(450-900 nm)and facilitated the charge transfer and separation.This study transforms waste into a high-efficient catalyst,realizing high-valued utilization of waste and environmental protection.

Conjugated polymerized bimetallic phthalocyanine based electrocatalyst with Fe-N_(4)/Co-N_(4) dual-sites synergistic effect for zinc-air battery

The bifunctional oxygen catalyst is essential for zinc-air batteries(ZABs).Here,an efficient bifunctional oxygen catalyst,PPcFeCo/3D-G,is obtained throughπ-πinteraction between the conjugated polymerized iron-cobalt phthalocyanine(PPcFeCo)with excellent thermal stability and three-dimensional graphene(3D-G).The bimetallic synergistic effect of PPcFeCo,verified by DFT(Density functional theory)calculation,andπ-πinteractions enhances the catalytic activity and durability of the PPcFeCo/3D-G.Regarding electrochemical performance,the PPcFeCo/3D-G with a high electron transfer number(3.98,@0.768 V vs.RHE)has excellent half-wave potential(E_(1/2)=0.890 V vs.RHE)and exhibits outstanding reversibility(ΔE=0.700 V,ΔE=Ej=10-E_(1/2)).The liquid ZAB(LZAB)employed PPcFeCo/3D-G displays a high power density(222 m W cm^(-2)),a specific capacity(792 m A h g-1),and excellent durability(120 h).This work has guiding significance for the preparation of high-efficiency bifunctional catalysts.

Synergies and trade-offs of climate-smart agriculture(CSA)practices selected by smallholder farmers in Geshy watershed,Southwest Ethiopia

Studies on mainstreaming climate-smart agriculture(CSA)practices can increase smallholder farmers’capacity and awareness to improve food security and establish sustainable livelihoods through resilient agricultural systems,while achieving adaptation and mitigation benefits.Hence,valuable insights can be obtained from smallholder farmers in responding to present and forthcoming challenges of climate change impacts.However,there is little research work on trade-off and synergy assessments.Taking Geshy watershed in Southwest Ethiopia as a case study area,both quantitative and qualitative data analysis were undertaken in this study.The data were collected from 15 key informant interviews,6 focus group discussions,and 384 households to answer the following questions:(1)what are the top 5 preferred CSA practices for smallholder farmers in Geshy watershed when coping with the impacts of climate change?(2)What is the performance of the preferred CSA practices?And(3)which trade-offs and synergies are experienced upon the implementation of CSA practices?The study came up with the most preferred CSA practices such as the use of improved crop varieties,small-scale irrigation,improved animal husbandry,the use of efficient inorganic fertilizers,and crop rotation with legumes.The selected CSA practices showed that the productivity goal exhibit the best synergy,while the mitigation goal has trade-offs.The study also indicated that the use of improved crop varieties causes high synergies in all 3 goals of CSA practices;small-scale irrigation provides a medium synergy on productivity goal but high synergy for adaptation and mitigation goals;improved animal husbandry shows a high synergy with the adaptation goal,a relatively lower synergy with the productivity goal,and a trade-off with the mitigation goal;the use of efficient inorganic fertilizers shows maximum synergy for the productivity and adaptation goals;and crop rotation with legumes exhibits high synergy with the productivity and mitigation goals but a relatively lower synergy with the adaptation goal.These results can provide evidence to various stakeholder farmers in the value chain that the impacts of climate change can be addressed by the adoption of CSA practices.In general,CSA practices are considered indispensable.Smallholder farmers prefer CSA practices that help to increase crop productivity and household resilience to climate change impacts.The results generate a vital foundation for recommendations to smallholder farming decision-makers.It also sensitizes actions for innovative and sustainable methods that are able to upscale the preferred CSA practices in the agricultural system in Geshy watershed of Southwest Ethiopia and other regions.