Magnesium alloy is a promising biodegradable metal material for hard tissue engineering.However,its high corrosion rate limits its application.In our previous study,we biomimetically deposited a calcium carbonate coat...Magnesium alloy is a promising biodegradable metal material for hard tissue engineering.However,its high corrosion rate limits its application.In our previous study,we biomimetically deposited a calcium carbonate coating on the surface of magnesium alloy using siloxane induction.This calcium carbonate coating demonstrated excellent in vitro biocompatibility and provided partial protection for the magnesium alloy substrate.In this study,we further enhanced the corrosion resistance of the calcium carbonate coating by treating it with stearic acid and its derivative,sodium stearate.Electrochemical corrosion tests revealed that the sodium stearate-treated calcium carbonate coating reduced the corrosion rate by two orders of magnitude.Additionally,in vitro biocompatibility assessments showed that while the biocompatibility of the sodium stearate-treated coating was slightly reduced,it remained acceptable compared to the magnesium substrate.This study builds on our previous work and offers a promising reinforcement strategy for degradable magnesium alloys in medical applications.展开更多
Ouricuri endocarp was utilized as a biosorbent for the recovery of europium(Eu(Ⅲ))from aqueous solutions and rare earth elements(REEs)from authentic leachate derived from phosphogypsum,which encompasses various REEs....Ouricuri endocarp was utilized as a biosorbent for the recovery of europium(Eu(Ⅲ))from aqueous solutions and rare earth elements(REEs)from authentic leachate derived from phosphogypsum,which encompasses various REEs.Various characterization techniques were applied to analyze the physicochemical and adsorptive properties of the biosorbent.The results indicate that the adsorption kinetic data conform well to the pseudo-first-order model,while the Liu model describes the equilibrium data well.Ouricuri endocarp and Eu interactions are favorable and spontaneous.The maximum adsorption capacity for Eu(Ⅲ)is determined to be 22.9 mg/g according to the Liu model.Based on experimental results and adsorbent characteristics,the proposed adsorption mechanisms between ouricuri endocarp and Eu include ion exchange and electrostatic interactions as the primary mechanisms.The Eu(Ⅲ)recovery is also feasible as a continuous flow process demonstrating inclined breakthrough curves and lower values of the length of the mass transfer zone.Ouricuri endocarp demonstrates its selectivity for recovering various REEs from authentic phosphogypsum leachate.It achieves a 98%recovery rate for Eu and approximately 60%for Ce,La,and Nd,affirming its efficacy under real-world conditions.Finally,concentration of REE was done by ashing loaded ouricuri endocarp,and a solid with around 34%(in weight)of REE is obtained.展开更多
The growth of computing power in data centers(DCs)leads to an increase in energy consumption and noise pollution of air cooling systems.Chip-level cooling with high-efficiency coolant is one of the promising methods t...The growth of computing power in data centers(DCs)leads to an increase in energy consumption and noise pollution of air cooling systems.Chip-level cooling with high-efficiency coolant is one of the promising methods to address the cooling challenge for high-power devices in DCs.Hybrid nanofluid(HNF)has the advantages of high thermal conductivity and good rheological properties.This study summarizes the numerical investigations of HNFs in mini/micro heat sinks,including the numerical methods,hydrothermal characteristics,and enhanced heat transfer technologies.The innovations of this paper include:(1)the characteristics,applicable conditions,and scenarios of each theoretical method and numerical method are clarified;(2)the molecular dynamics(MD)simulation can reveal the synergy effect,micro motion,and agglomeration morphology of different nanoparticles.Machine learning(ML)presents a feasiblemethod for parameter prediction,which provides the opportunity for the intelligent regulation of the thermal performance of HNFs;(3)the HNFs flowboiling and the synergy of passive and active technologies may further improve the overall efficiency of liquid cooling systems in DCs.This review provides valuable insights and references for exploring the multi-phase flow and heat transport mechanisms of HNFs,and promoting the practical application of HNFs in chip-level liquid cooling in DCs.展开更多
Mediterranean forest communities are particularly diverse but at risk due to their sensitivity to global warming.Understanding the long-term vulnerability of Mediterranean vegetation to climate change is crucial for c...Mediterranean forest communities are particularly diverse but at risk due to their sensitivity to global warming.Understanding the long-term vulnerability of Mediterranean vegetation to climate change is crucial for conservation and management purposes.Studies on past changes of forest communities in response to climate change at ecologically meaningful resolutions(i.e.,decadal time scales) are therefore essential,but still very rare.The Holocene thermal maximum(HTM;ca.10,000-5,000 cal years before the present(BP)) may be used to study species and community responses to warmer conditions than during recent decades.We performed highresolution multiproxy palaeoecological analyses on sediments from crater Lake Mezzano in central Italy to reconstruct vegetation,diversity,and fire dynamics between 8,450 and 7,050 cal years BP.Ordination,crosscorrelation,and species-response analyses were used to investigate the response of Mediterranean forest communities to HTM climate warming,human impact,and fire.Vegetational changes prior to 7,450 cal years BP were driven by climate.Fagus sylvatica spread into mixed deciduous oak forests during the Early Holocene in response to declining seasonality(cooler summers and warmer winters).Subsequently,Fagus sylvatica declined and evergreen Quercus ilex expanded after 8,200 cal years BP when the climate became warmer.Although reduced,Fagus sylvatica remained important together with deciduous oaks.The co-existence of Fagus sylvatica and evergreen Quercus forests is extremely rare today.Human impact significantly affected forest vegetation after7,450 cal years BP,when Neolithic agricultural activities became important,ultimately extirpating these special communities but fostering the overall biodiversity.However,their past occurrence in several central Italian calderas during the HTM suggests that these environments provided habitats that permitted the thriving of cooltemperate forests of Fagus sylvatica under mesomediterranean conditions,with summers ca.1-2℃ warmer than today.Cool and moist calderas may thus become increasingly important for maintaining Mediterranean mesophilous forest species under global warming conditions.展开更多
It is challenging to efficiently and economically recycle many lithium-ion batteries(LIBs)because of the low valuation of commodity metals and materials,such as LiFePO_(4).There are millions of tons of spent LIBs wher...It is challenging to efficiently and economically recycle many lithium-ion batteries(LIBs)because of the low valuation of commodity metals and materials,such as LiFePO_(4).There are millions of tons of spent LIBs where the barrier to recycling is economical,and to make recycling more feasible,it is required that the value of the processed recycled material exceeds the value of raw commodity materials.The presented research illustrates improved profitability and economics for recycling spent LIBs by utilizing the surplus energy in lithiated graphite to drive the preparation of organolithiums to add value to the recycled lithium materials.This study methodology demonstrates that the surplus energy of lithiated graphite obtained from spent LIBs can be utilized to prepare high-value organolithiums,thereby significantly improving the economic profitability of LIB recycling.Organolithiums(R-O-Li and R-Li)were prepared using alkyl alcohol(R-OH)and alkyl bromide(R-Br)as substrates,where R includes varying hindered alkyl hydrocarbons.The organolithiums extracted from per kilogram of recycled LIBs can increase the economic value between$29.5 and$226.5 kg^(−1) cell.The value of the organolithiums is at least 5.4 times the total theoretical value of spent materials,improving the profitability of recycling LIBs over traditional pyrometallurgical($0.86 kg^(−1) cell),hydrometallurgical($1.00 kg^(−1) cell),and physical direct recycling methods($5.40 kg^(−1) cell).展开更多
Owing to their high theoretical specific capacity and low cost, lithium- and manganese-rich layered oxide (LMR) cathode materials are receiving increasing attention for application in lithium-ion batteries. However, p...Owing to their high theoretical specific capacity and low cost, lithium- and manganese-rich layered oxide (LMR) cathode materials are receiving increasing attention for application in lithium-ion batteries. However, poor lithium ion and electron transport kinetics plus side effects of anion and cation redox reactions hamper power performance and stability of the LMRs. In this study, LMR Li_(1.2)Mn_(0.6)Ni_(0.2)O_(2) was modified by phosphorus (P)-doping to increase Li+ conductivity in the bulk material. This was achieved by increasing the interlayer spacing of the lithium layer, electron transport and structural stability, resulting in improvement of the rate and safety performance. P^(5+) doping increased the distance between the (003) crystal planes from ~0.474 nm to 0.488 nm and enhanced the structural stability by forming strong covalent bonds with oxygen atoms, resulting in an improved rate performance (capacity retention from 38% to 50% at 0.05 C to 5 C) and thermal stability (50% heat release compared with pristine material). First-principles calculations showed the P-doping makes the transfer of excited electrons from the valence band to conduction band easier and P can form a strong covalent bond helping to stabilize material structure. Furthermore, the solid-state electrolyte modified P5+ doped LMR showed an improved cycle performance for up to 200 cycles with capacity retention of 90.5% and enhanced initial coulombic efficiency from 68.5% (pristine) or 81.7% (P-doped LMR) to 88.7%.展开更多
The first report of new 3-(tetrazol-5-yl)-2-iminocoumarin derivatives is described. The title compounds were prepared in two steps and were obtained in good yields (55-93%). They have been fully characterized by <s...The first report of new 3-(tetrazol-5-yl)-2-iminocoumarin derivatives is described. The title compounds were prepared in two steps and were obtained in good yields (55-93%). They have been fully characterized by <sup>1</sup>H, <sup>13</sup>C NMR, FTIR, UV-Visible and HRMS. They were tested for their antiproliferative activities against six representative human tumor cell lines (Huh 7-D12, Caco2, MDA-MB231, HCT 116, PC3 and NCI-H727) and HaCat keratinocytes. Among them, compound 5e was active on HCT 116 (IC<sub>50</sub> 15 μM).展开更多
Efficient and reliable energy storage systems are crucial for our modern society.Lithium-ion batteries(LIBs)with excellent performance are widely used in portable electronics and electric vehicles(EVs),but frequent fi...Efficient and reliable energy storage systems are crucial for our modern society.Lithium-ion batteries(LIBs)with excellent performance are widely used in portable electronics and electric vehicles(EVs),but frequent fires and explosions limit their further and more widespread applications.This review summarizes aspects of LIB safety and discusses the related issues,strategies,and testing standards.Specifically,it begins with a brief introduction to LIB working principles and cell structures,and then provides an overview of the notorious thermal runaway,with an emphasis on the effects of mechanical,electrical,and thermal abuse.The following sections examine strategies for improving cell safety,including approaches through cell chemistry,cooling,and balancing,afterwards describing current safety standards and corresponding tests.The review concludes with insights into potential future developments and the prospects for safer LIBs.展开更多
In early 2018,the Boliden Garpenberg operation implemented an optimized control strategy as an addition to the existing ventilation on demand system.The purpose of the strategy is to further minimize energy use for ma...In early 2018,the Boliden Garpenberg operation implemented an optimized control strategy as an addition to the existing ventilation on demand system.The purpose of the strategy is to further minimize energy use for main and booster fans,whilst also fulfilling airflow setpoints without violating constraints such as min/max differential pressure over fans and interaction of air between areas in mines.Using air flow measurements and a dynamical model of the ventilation system,a mine-wide coordination control of fans can be carried out.The numerical model is data driven and derived from historical operational data or step changes experiments.This makes both initial deployment and lifetime model maintenance,as the mine evolves,a comparably easy operation.The control has been proven to operate in a stable manner over long periods without having to re-calibrate the model.Results prove a 40%decrease in energy use for the fans involved and a greater controllability of air flow.Moreover,a 15%decrease of the total air flow into the mine will give additional proportional heating savings during winter periods.All in all,the multivariable controller shows a correlation between production in the mine and the ventilation system performance superior to all of its predecessors.展开更多
Nitrogen oxides(NOx:NO,NO2)are a concern due to their adverse health effects.Diesel engine transport sector is the major emitter of NOx.The regulations have been strengthened and to comply with them,one of the two ...Nitrogen oxides(NOx:NO,NO2)are a concern due to their adverse health effects.Diesel engine transport sector is the major emitter of NOx.The regulations have been strengthened and to comply with them,one of the two methods commonly used is the selective catalytic reduction of NOxby NH3(NH3-SCR),NH3being supplied by the in-situ hydrolysis of urea.Efficiency and durability of the catalyst for this process are highly required.Durability is evaluated by hydrothermal treatment of the catalysts at temperature above 800℃.In this study,very active catalysts for the NH3-SCR of NOxwere prepared by using a silicoaluminophosphate commercial zeolite as copper host structure.Characterizations by X-ray diffraction(XRD),scanning electron microscopy(SEM)and temperature programmed desorption of ammonia(NH3-TPD)showed that this commercial zeolite was hydrothermally stable up to 850℃ and,was able to retain some structural properties up to950℃.After hydrothermal treatment at 850℃,the NOxreduction efficiency into NH3-SCR depends on the copper content.The catalyst with a copper content of 1.25 wt.%was the most active.The difference in activity was much more important when using NO than the fast NO/NO2reaction mixture.展开更多
Pea aphid,Acyrthosiphon pisum,is a serious pest of many different leguminous plants,and it mainly relies on its odorant receptors(Ors)to discriminate among host species.However,less is known about the role that Ors pl...Pea aphid,Acyrthosiphon pisum,is a serious pest of many different leguminous plants,and it mainly relies on its odorant receptors(Ors)to discriminate among host species.However,less is known about the role that Ors play in the host plant location.In this study,we identified a novel conserved odorant receptor clade by phylogenetic analysis,and conducted the functional analysis of ApisOr23 in A.pisum.The results showed that the homologous Ors from A.pisum,Aphis glycines and Aphis gossypii share 94.28% identity in amino acid sequences.Moreover,conserved motifs were analyzed using the annotated homologous Or23 from eight aphid species,providing further proof of the high conservation level of the Or23 clade.According to the tissue expression pattern analysis,ApisOr23 was mainly expressed in the antennae.Further functional study using a heterologous Xenopus expression system revealed that ApisOr23 was tuned to five plant volatiles,namely trans-2-hexen-1-al,cis-2-hexen-1-ol,1-heptanol,4’-ethylacetophenone,and hexyl acetate.Among them,trans-2-hexen-1-al,which is one of the main volatile organic compounds released from legume plants,activated the highest response of ApisOr23.Our findings suggest that the conserved Or23 clade in most aphid species might play an important role in host plant detection.展开更多
Few effective treatments for chronic Keshan disease have been available till now.The efficacy of long-term selenium supplementation in the treatment of chronic Keshan disease with congestive heart failure is inconclus...Few effective treatments for chronic Keshan disease have been available till now.The efficacy of long-term selenium supplementation in the treatment of chronic Keshan disease with congestive heart failure is inconclusive.This study aimed to determine whether selenium supplementation is associated with a decreased risk of cardiac death in chronic Keshan disease with congestive heart failure by ten years of follow-up.A retrospective long-term follow-up analysis was performed on a monitored cohort consisting of 302 chronic Keshan disease patients with a mean age of 40.8±11.4 years.Of the 302 chronic Keshan disease patients,170(56.3%)were given selenium supplementation until the end point of follow-up.Cox proportional hazards regression models were used to identify the independent predictors of cardiac events.Our results showed that during the follow-up,there were 101 deaths of patients with chronic Keshan disease in the selenium supplementation group(101/170,59.4%)and 98 in non-selenium supplementation group(98/132,74.2%).Multivariate analyses suggested that selenium supplementation was associated with a decreased risk of cardiac death(HR 0.39,95%CI 0.28-0.53)after adjustment for baseline age,sex,cigarette smoking,family history of Keshan disease,body mass index(BMI),heart rate,electrocardiogram(ECG)abnonnalities,blood pressure,initial cardiothoracic ratio,left ventricular可ection fractions(LVEF)and whole-blood selenium concentration.Our ten-year follow-up analysis indicated that selenium supplementation,specifically combined with the use of angiotensinconverting cnzyme inhibitor and beta blocker therapy,improved the survival of patients with chronic Keshan disease with congestive heart failure.BMI,selenium deficiency,male,combined ECG abnonnalities,LVEF,and fast heart rate increased the risk of cardiac events.展开更多
In this study,vine pruning wastes(VPW)were used as raw material to develop an alternative activated carbon(VPW-AC)for adsorbing and concentrating rare earth elements cerium(Ce(Ⅲ))and lanthanum(La(Ⅲ))from synthetic a...In this study,vine pruning wastes(VPW)were used as raw material to develop an alternative activated carbon(VPW-AC)for adsorbing and concentrating rare earth elements cerium(Ce(Ⅲ))and lanthanum(La(Ⅲ))from synthetic and real leachate solutions.The Ce and La adsorption studies evaluated the effects of VPW-AC dosage,pH,contact time,rare earth initial concentration,and temperature.The VPW-AC adsorbent was subjected to many physicochemical characterization methods to correlate and understand its adsorptive performance.The characterization data indicate a carbonaceous adsorbent with a specific surface area of 467 m^(2)/g.Zeta potential indicates a material with a negatively charged surface at a pH higher than 3.1,which is extremely beneficial to cations removal.For both rare earths elements(REEs),the adsorption capacity increases with the increase of the pH,reaching its maximum at pH 4-6.The kinetic data are well fitted by Avrami-fractional o rder,while the Liu model agreeably fits equilibrium data.The maximum adsorption capacities for Ce(Ⅲ)and La(Ⅲ)are 48.45 and 53.65 mg/g at 298 K,respectively.The thermodynamic studies suggest that the adsorption process is favorable,spontaneous,and exothermic for both REEs.Pore filling,surface complexation,and ion exchange are the dominant mechanisms.Finally,the VPW-AC was subjected to the recovery of REEs from real phosphogypsum leachate,and it is proved that it can be successfully used to recover REEs in a real process.展开更多
The anther-smut Microbotryum violaceum ( Brandenburger and Schvinn) G. Deml. and Oberw.) causes a systematic infection of its host Silene dioica ( L.) Clairv., resulting in sterility and production of teliospores (dis...The anther-smut Microbotryum violaceum ( Brandenburger and Schvinn) G. Deml. and Oberw.) causes a systematic infection of its host Silene dioica ( L.) Clairv., resulting in sterility and production of teliospores (dispersal propagules) in flowers. These spores are transmitted to healthy plants mainly by flower visitors. The behavioral responses of flower visitors to a variation in floral characters are not only likely to affect rates of pollen export/import, but also the rate of spore deposition and probability of disease. In a transplantation experiment, using plants from four different populations, we tested for correlation between variation in female floral morphology and patterns of spore and pollen deposition, and a resulting risk of disease. The source populations in this experiment were located on four islands in Skeppsvik archipelago in northern Sweden, and represented a gradient of disease incidence from completely healthy ( Island 1), low incidence ( Island 2) to high incidences ( Islands 3 and 4) of disease. Fifty plants from each population were transplanted to the center, of the population on Island 4. There were significant differences among the transplants in floral characters, i.e. corolla size, style length and ovule number. Plants from the non-diseased population had larger flowers and longer styles than plants from the highly diseased populations. Numbers of pollen grains and spores deposited on flowers were strongly and positively correlated. We found that plants originating from the non-diseased population captured approximately 4 times more pollen and 9 times more spores, per flower than die individuals from the resident population (Island 4, population 4). The incidences of disease among plants, from the four populations differed significantly, and was 37%, 20%, 18% and 0 for populations 1, 2, 3 and 4 respectively. In a survey of ten populations we found a significant negative correlation between the mean style length ( positively correlated with corolla size and ovule number) among healthy plants and incidence of disease in these populations. The potentiality for pathogen-pollinator mediated selection oil floral characters; and consequences for gone flow between populations of Silene dioica are discussed.展开更多
Dear Editor,Johannes Lehmann and Markus Kleber,in a controversial paper entitled"The contentious nature of soil organic matter"(Lehmann and Kleber,2015),suggested the abandonment of the term"humus"...Dear Editor,Johannes Lehmann and Markus Kleber,in a controversial paper entitled"The contentious nature of soil organic matter"(Lehmann and Kleber,2015),suggested the abandonment of the term"humus"and other associated terms such as"humic","humir","humified","humification".The first reason they cited was that these labels are only instrumental in outdated soil analytical methods,which are based on alkaline extraction of soil organic matter(SOM).展开更多
Background: Investigating population ecology of urban bird species,particularly the invasive and expending spe?cies,is the key for the success of urban management and planning strategies.Methods: Populations of two Co...Background: Investigating population ecology of urban bird species,particularly the invasive and expending spe?cies,is the key for the success of urban management and planning strategies.Methods: Populations of two Columbidae species,the Woodpigeon(Columba palumbus) and the Eurasian Collared Dove(Streptopelia decaocto),were monitored from 1992 to 2010 in the Algiers Sahel,the Mitidja Plain and surround?ing areas(Northern Algeria).Monitoring of species densities was performed by the mapping?plot method.The foraging flight routes of Woodpigeon and the distribution of Eurasian Collared Dove were assessed by systematic observations.Results: The number of counted birds was statistically constant at first years of the survey,and then increased sig?nificantly,beginning from low numbers,their densities accelerated sharply between 2001 and 2006,then reached to an equilibrium state.The significant increase in Woodpigeon's population could be explained by the reduced hunt?ing pressure and by species adaptation to new food resources provided by nearby agriculture.Indeed,monitoring of flight directions of the species revealed the use of agricultural landscapes and habitats,which is a good indicator explaining adaptation and trophic niche of the species.The occurrence of the Eurasian Collared Dove in Algiers began in 2000.Its density experienced a rapid increase with similar trend pattern as that of Woodpigeon.Its distributional range is confined mainly in suburban environments of the Mitidja Plain.Conclusion: The modifications of habitats,urbanization increase and the lessening of hunting in the Mitidja Plain facilitated the rapid expansion of the Eurasian Collared Dove and Woodpigeon as well contributed to the increase in their numbers over time.展开更多
Two polymeric complexes, [Cd(BTP)2]n 1 and [Cd(i-BTP)2]n 2, were prepared and investigated by solid 31P and 113Cd NMR spectroscopies. The crystal structure of 2 was determined by X-ray diffraction.
Objective:To determine the genetic diversity of Plasmodium(P.)knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia,targeting the S-type SSU rRNA gene and including aspects of natural selection and hap...Objective:To determine the genetic diversity of Plasmodium(P.)knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia,targeting the S-type SSU rRNA gene and including aspects of natural selection and haplotype.Methods:Thirty-nine blood samples infected with P.knowlesi were collected in Sabah,Malaysian Borneo and Peninsular Malaysia.The S-type SSU rRNA gene was amplified using polymerase chain reaction,cloned into a vector,and sequenced.The natural selection and haplotype of the S-type SSU rRNA gene sequences were determined using DnaSP v6 and illustrated using NETWORK v10.This study's 39 S-type SSU rRNA sequences and eight sequences from the Genbank database were subjected to phylogenetic analysis using MEGA 11.Results:Overall,the phylogenetic analysis showed no evidence of a geographical cluster of P.knowlesi isolates from different areas in Malaysia based on the S-type SSU rRNA gene sequences.The S-type SSU rRNA gene sequences were relatively conserved and with a purifying effect.Haplotype sharing of the S-type SSU rRNA gene was observed between the P.knowlesi isolates in Sabah,Malaysian Borneo,but not between Sabah,Malaysian Borneo and Peninsular Malaysia.Conclusions:This study suggests that the S-type SSU rRNA gene of P.knowlesi isolates in Sabah,Malaysian Borneo,and Peninsular Malaysia has fewer polymorphic sites,representing the conservation of the gene.These features make the S-type SSU rRNA gene suitable for comparative studies,such as determining the evolutionary relationships and common ancestry among P.knowlesi species.展开更多
Non-equilibrium solidification structures of Cu55Ni45 and Cu55Ni43Co2 alloys were prepared by the molten glass purification cycle superheating method.The variation of the recalescence phenomenon with the degree of und...Non-equilibrium solidification structures of Cu55Ni45 and Cu55Ni43Co2 alloys were prepared by the molten glass purification cycle superheating method.The variation of the recalescence phenomenon with the degree of undercooling in the rapid solidification process was investigated using an infrared thermometer.The addition of the Co element affected the evolution of the recalescence phenomenon in Cu-Ni alloys.The images of the solid-liquid interface migration during the rapid solidification of supercooled melts were captured by using a high-speed camera.The solidification rate of Cu-Ni alloys,with the addition of Co elements,was explored.Finally,the grain refinement structure with low supercooling was characterised using electron backscatter diffraction(EBSD).The effect of Co on the microstructural evolution during nonequilibrium solidification of Cu-Ni alloys under conditions of small supercooling is investigated by comparing the microstructures of Cu55Ni45 and Cu55Ni43Co2 alloys.The experimental results show that the addition of a small amount of Co weakens the recalescence behaviour of the Cu55Ni45 alloy and significantly reduces the thermal strain in the rapid solidification phase.In the rapid solidification phase,the thermal strain is greatly reduced,and there is a significant increase in the characteristic undercooling degree.Furthermore,the addition of Co and the reduction of Cu not only result in a lower solidification rate of the alloy,but also contribute to the homogenisation of the grain size.展开更多
基金supported by the National Natural Science Foundation of China(No.52205310)the TUA research funding,UmeåUniversity/Region Västerbotten,Sweden(RV-937838)+1 种基金the Kempe foundation(JCSMK22-0122)the Natural Science Foundation of Shandong Province(No.ZR2021QE263).
文摘Magnesium alloy is a promising biodegradable metal material for hard tissue engineering.However,its high corrosion rate limits its application.In our previous study,we biomimetically deposited a calcium carbonate coating on the surface of magnesium alloy using siloxane induction.This calcium carbonate coating demonstrated excellent in vitro biocompatibility and provided partial protection for the magnesium alloy substrate.In this study,we further enhanced the corrosion resistance of the calcium carbonate coating by treating it with stearic acid and its derivative,sodium stearate.Electrochemical corrosion tests revealed that the sodium stearate-treated calcium carbonate coating reduced the corrosion rate by two orders of magnitude.Additionally,in vitro biocompatibility assessments showed that while the biocompatibility of the sodium stearate-treated coating was slightly reduced,it remained acceptable compared to the magnesium substrate.This study builds on our previous work and offers a promising reinforcement strategy for degradable magnesium alloys in medical applications.
基金Project supported by the Brazilian National Council for Scientific and Technological Development/CNPq(405982/2022-4 and 303992/2021-2)。
文摘Ouricuri endocarp was utilized as a biosorbent for the recovery of europium(Eu(Ⅲ))from aqueous solutions and rare earth elements(REEs)from authentic leachate derived from phosphogypsum,which encompasses various REEs.Various characterization techniques were applied to analyze the physicochemical and adsorptive properties of the biosorbent.The results indicate that the adsorption kinetic data conform well to the pseudo-first-order model,while the Liu model describes the equilibrium data well.Ouricuri endocarp and Eu interactions are favorable and spontaneous.The maximum adsorption capacity for Eu(Ⅲ)is determined to be 22.9 mg/g according to the Liu model.Based on experimental results and adsorbent characteristics,the proposed adsorption mechanisms between ouricuri endocarp and Eu include ion exchange and electrostatic interactions as the primary mechanisms.The Eu(Ⅲ)recovery is also feasible as a continuous flow process demonstrating inclined breakthrough curves and lower values of the length of the mass transfer zone.Ouricuri endocarp demonstrates its selectivity for recovering various REEs from authentic phosphogypsum leachate.It achieves a 98%recovery rate for Eu and approximately 60%for Ce,La,and Nd,affirming its efficacy under real-world conditions.Finally,concentration of REE was done by ashing loaded ouricuri endocarp,and a solid with around 34%(in weight)of REE is obtained.
基金funded by the Science and Technology Project of Tianjin(No.24YDTPJC00680)the National Natural Science Foundation of China(No.52406191).
文摘The growth of computing power in data centers(DCs)leads to an increase in energy consumption and noise pollution of air cooling systems.Chip-level cooling with high-efficiency coolant is one of the promising methods to address the cooling challenge for high-power devices in DCs.Hybrid nanofluid(HNF)has the advantages of high thermal conductivity and good rheological properties.This study summarizes the numerical investigations of HNFs in mini/micro heat sinks,including the numerical methods,hydrothermal characteristics,and enhanced heat transfer technologies.The innovations of this paper include:(1)the characteristics,applicable conditions,and scenarios of each theoretical method and numerical method are clarified;(2)the molecular dynamics(MD)simulation can reveal the synergy effect,micro motion,and agglomeration morphology of different nanoparticles.Machine learning(ML)presents a feasiblemethod for parameter prediction,which provides the opportunity for the intelligent regulation of the thermal performance of HNFs;(3)the HNFs flowboiling and the synergy of passive and active technologies may further improve the overall efficiency of liquid cooling systems in DCs.This review provides valuable insights and references for exploring the multi-phase flow and heat transport mechanisms of HNFs,and promoting the practical application of HNFs in chip-level liquid cooling in DCs.
基金funded by the Swiss National Science Foundation(SNF 200020_182084).
文摘Mediterranean forest communities are particularly diverse but at risk due to their sensitivity to global warming.Understanding the long-term vulnerability of Mediterranean vegetation to climate change is crucial for conservation and management purposes.Studies on past changes of forest communities in response to climate change at ecologically meaningful resolutions(i.e.,decadal time scales) are therefore essential,but still very rare.The Holocene thermal maximum(HTM;ca.10,000-5,000 cal years before the present(BP)) may be used to study species and community responses to warmer conditions than during recent decades.We performed highresolution multiproxy palaeoecological analyses on sediments from crater Lake Mezzano in central Italy to reconstruct vegetation,diversity,and fire dynamics between 8,450 and 7,050 cal years BP.Ordination,crosscorrelation,and species-response analyses were used to investigate the response of Mediterranean forest communities to HTM climate warming,human impact,and fire.Vegetational changes prior to 7,450 cal years BP were driven by climate.Fagus sylvatica spread into mixed deciduous oak forests during the Early Holocene in response to declining seasonality(cooler summers and warmer winters).Subsequently,Fagus sylvatica declined and evergreen Quercus ilex expanded after 8,200 cal years BP when the climate became warmer.Although reduced,Fagus sylvatica remained important together with deciduous oaks.The co-existence of Fagus sylvatica and evergreen Quercus forests is extremely rare today.Human impact significantly affected forest vegetation after7,450 cal years BP,when Neolithic agricultural activities became important,ultimately extirpating these special communities but fostering the overall biodiversity.However,their past occurrence in several central Italian calderas during the HTM suggests that these environments provided habitats that permitted the thriving of cooltemperate forests of Fagus sylvatica under mesomediterranean conditions,with summers ca.1-2℃ warmer than today.Cool and moist calderas may thus become increasingly important for maintaining Mediterranean mesophilous forest species under global warming conditions.
基金National Natural Science Foundation of China,Grant/Award Number:51232005Key-Area Research and Development Program of Guangdong Province,Grant/Award Number:2020B090919003+1 种基金Joint Fund of the National Natural Science Foundation of China,Grant/Award Number:U1401243Shenzhen Technical Plan Project,Grant/Award Number:CYJ20170412170911187。
文摘It is challenging to efficiently and economically recycle many lithium-ion batteries(LIBs)because of the low valuation of commodity metals and materials,such as LiFePO_(4).There are millions of tons of spent LIBs where the barrier to recycling is economical,and to make recycling more feasible,it is required that the value of the processed recycled material exceeds the value of raw commodity materials.The presented research illustrates improved profitability and economics for recycling spent LIBs by utilizing the surplus energy in lithiated graphite to drive the preparation of organolithiums to add value to the recycled lithium materials.This study methodology demonstrates that the surplus energy of lithiated graphite obtained from spent LIBs can be utilized to prepare high-value organolithiums,thereby significantly improving the economic profitability of LIB recycling.Organolithiums(R-O-Li and R-Li)were prepared using alkyl alcohol(R-OH)and alkyl bromide(R-Br)as substrates,where R includes varying hindered alkyl hydrocarbons.The organolithiums extracted from per kilogram of recycled LIBs can increase the economic value between$29.5 and$226.5 kg^(−1) cell.The value of the organolithiums is at least 5.4 times the total theoretical value of spent materials,improving the profitability of recycling LIBs over traditional pyrometallurgical($0.86 kg^(−1) cell),hydrometallurgical($1.00 kg^(−1) cell),and physical direct recycling methods($5.40 kg^(−1) cell).
基金This work was supported by the National Natural Science Foundation of China(U1564205)the Project of Construction of Innovative Teams and Teacher Career Development for Universities and Colleges under the Beijing Municipality(IDHT20180508).Naser Tavajohi acknowledges financial support from the Kempe Foundation.
文摘Owing to their high theoretical specific capacity and low cost, lithium- and manganese-rich layered oxide (LMR) cathode materials are receiving increasing attention for application in lithium-ion batteries. However, poor lithium ion and electron transport kinetics plus side effects of anion and cation redox reactions hamper power performance and stability of the LMRs. In this study, LMR Li_(1.2)Mn_(0.6)Ni_(0.2)O_(2) was modified by phosphorus (P)-doping to increase Li+ conductivity in the bulk material. This was achieved by increasing the interlayer spacing of the lithium layer, electron transport and structural stability, resulting in improvement of the rate and safety performance. P^(5+) doping increased the distance between the (003) crystal planes from ~0.474 nm to 0.488 nm and enhanced the structural stability by forming strong covalent bonds with oxygen atoms, resulting in an improved rate performance (capacity retention from 38% to 50% at 0.05 C to 5 C) and thermal stability (50% heat release compared with pristine material). First-principles calculations showed the P-doping makes the transfer of excited electrons from the valence band to conduction band easier and P can form a strong covalent bond helping to stabilize material structure. Furthermore, the solid-state electrolyte modified P5+ doped LMR showed an improved cycle performance for up to 200 cycles with capacity retention of 90.5% and enhanced initial coulombic efficiency from 68.5% (pristine) or 81.7% (P-doped LMR) to 88.7%.
文摘The first report of new 3-(tetrazol-5-yl)-2-iminocoumarin derivatives is described. The title compounds were prepared in two steps and were obtained in good yields (55-93%). They have been fully characterized by <sup>1</sup>H, <sup>13</sup>C NMR, FTIR, UV-Visible and HRMS. They were tested for their antiproliferative activities against six representative human tumor cell lines (Huh 7-D12, Caco2, MDA-MB231, HCT 116, PC3 and NCI-H727) and HaCat keratinocytes. Among them, compound 5e was active on HCT 116 (IC<sub>50</sub> 15 μM).
基金financially supported by the National Key Basic Research Program of China(No.2014CB932400)the Joint Fund of the National Natural Science Foundation of China(No.U1401243)+3 种基金the National Natural Science Foundation of China(No.51232005)the Shenzhen Technical Plan Project(No.JCYJ20150529164918735,CYJ20170412170911187,KQJSCX20160226191136)the Guangdong Technical Plan Project(No.2015TX01N011)the financial support by Bio4Energy program。
文摘Efficient and reliable energy storage systems are crucial for our modern society.Lithium-ion batteries(LIBs)with excellent performance are widely used in portable electronics and electric vehicles(EVs),but frequent fires and explosions limit their further and more widespread applications.This review summarizes aspects of LIB safety and discusses the related issues,strategies,and testing standards.Specifically,it begins with a brief introduction to LIB working principles and cell structures,and then provides an overview of the notorious thermal runaway,with an emphasis on the effects of mechanical,electrical,and thermal abuse.The following sections examine strategies for improving cell safety,including approaches through cell chemistry,cooling,and balancing,afterwards describing current safety standards and corresponding tests.The review concludes with insights into potential future developments and the prospects for safer LIBs.
文摘In early 2018,the Boliden Garpenberg operation implemented an optimized control strategy as an addition to the existing ventilation on demand system.The purpose of the strategy is to further minimize energy use for main and booster fans,whilst also fulfilling airflow setpoints without violating constraints such as min/max differential pressure over fans and interaction of air between areas in mines.Using air flow measurements and a dynamical model of the ventilation system,a mine-wide coordination control of fans can be carried out.The numerical model is data driven and derived from historical operational data or step changes experiments.This makes both initial deployment and lifetime model maintenance,as the mine evolves,a comparably easy operation.The control has been proven to operate in a stable manner over long periods without having to re-calibrate the model.Results prove a 40%decrease in energy use for the fans involved and a greater controllability of air flow.Moreover,a 15%decrease of the total air flow into the mine will give additional proportional heating savings during winter periods.All in all,the multivariable controller shows a correlation between production in the mine and the ventilation system performance superior to all of its predecessors.
基金the UREENOX project (ANR-11-VPTT-002) funded by the French ANR (L'Agence National de la Recherche)the French ANR for financial supportThe Institute of Chemistry of Poitiers (IC2MP) for the management of the UREENOX project
文摘Nitrogen oxides(NOx:NO,NO2)are a concern due to their adverse health effects.Diesel engine transport sector is the major emitter of NOx.The regulations have been strengthened and to comply with them,one of the two methods commonly used is the selective catalytic reduction of NOxby NH3(NH3-SCR),NH3being supplied by the in-situ hydrolysis of urea.Efficiency and durability of the catalyst for this process are highly required.Durability is evaluated by hydrothermal treatment of the catalysts at temperature above 800℃.In this study,very active catalysts for the NH3-SCR of NOxwere prepared by using a silicoaluminophosphate commercial zeolite as copper host structure.Characterizations by X-ray diffraction(XRD),scanning electron microscopy(SEM)and temperature programmed desorption of ammonia(NH3-TPD)showed that this commercial zeolite was hydrothermally stable up to 850℃ and,was able to retain some structural properties up to950℃.After hydrothermal treatment at 850℃,the NOxreduction efficiency into NH3-SCR depends on the copper content.The catalyst with a copper content of 1.25 wt.%was the most active.The difference in activity was much more important when using NO than the fast NO/NO2reaction mixture.
基金funded by the National Natural Science Foundation of China(31572072 and 31725023)the Intergovernmental International Science,Technology and Innovation Cooperation Key Project,China(2019YFE0105800)the Shenzhen Science and Technology Program,China(KQTD20180411143628272)。
文摘Pea aphid,Acyrthosiphon pisum,is a serious pest of many different leguminous plants,and it mainly relies on its odorant receptors(Ors)to discriminate among host species.However,less is known about the role that Ors play in the host plant location.In this study,we identified a novel conserved odorant receptor clade by phylogenetic analysis,and conducted the functional analysis of ApisOr23 in A.pisum.The results showed that the homologous Ors from A.pisum,Aphis glycines and Aphis gossypii share 94.28% identity in amino acid sequences.Moreover,conserved motifs were analyzed using the annotated homologous Or23 from eight aphid species,providing further proof of the high conservation level of the Or23 clade.According to the tissue expression pattern analysis,ApisOr23 was mainly expressed in the antennae.Further functional study using a heterologous Xenopus expression system revealed that ApisOr23 was tuned to five plant volatiles,namely trans-2-hexen-1-al,cis-2-hexen-1-ol,1-heptanol,4’-ethylacetophenone,and hexyl acetate.Among them,trans-2-hexen-1-al,which is one of the main volatile organic compounds released from legume plants,activated the highest response of ApisOr23.Our findings suggest that the conserved Or23 clade in most aphid species might play an important role in host plant detection.
基金the National Natural Science Foundation of China(Nos.81441016,81273008).
文摘Few effective treatments for chronic Keshan disease have been available till now.The efficacy of long-term selenium supplementation in the treatment of chronic Keshan disease with congestive heart failure is inconclusive.This study aimed to determine whether selenium supplementation is associated with a decreased risk of cardiac death in chronic Keshan disease with congestive heart failure by ten years of follow-up.A retrospective long-term follow-up analysis was performed on a monitored cohort consisting of 302 chronic Keshan disease patients with a mean age of 40.8±11.4 years.Of the 302 chronic Keshan disease patients,170(56.3%)were given selenium supplementation until the end point of follow-up.Cox proportional hazards regression models were used to identify the independent predictors of cardiac events.Our results showed that during the follow-up,there were 101 deaths of patients with chronic Keshan disease in the selenium supplementation group(101/170,59.4%)and 98 in non-selenium supplementation group(98/132,74.2%).Multivariate analyses suggested that selenium supplementation was associated with a decreased risk of cardiac death(HR 0.39,95%CI 0.28-0.53)after adjustment for baseline age,sex,cigarette smoking,family history of Keshan disease,body mass index(BMI),heart rate,electrocardiogram(ECG)abnonnalities,blood pressure,initial cardiothoracic ratio,left ventricular可ection fractions(LVEF)and whole-blood selenium concentration.Our ten-year follow-up analysis indicated that selenium supplementation,specifically combined with the use of angiotensinconverting cnzyme inhibitor and beta blocker therapy,improved the survival of patients with chronic Keshan disease with congestive heart failure.BMI,selenium deficiency,male,combined ECG abnonnalities,LVEF,and fast heart rate increased the risk of cardiac events.
基金Project supported by the Brazilian National Council for Scientific and Technological Development/CNPq(405982/2022—4,303992/2021-2)。
文摘In this study,vine pruning wastes(VPW)were used as raw material to develop an alternative activated carbon(VPW-AC)for adsorbing and concentrating rare earth elements cerium(Ce(Ⅲ))and lanthanum(La(Ⅲ))from synthetic and real leachate solutions.The Ce and La adsorption studies evaluated the effects of VPW-AC dosage,pH,contact time,rare earth initial concentration,and temperature.The VPW-AC adsorbent was subjected to many physicochemical characterization methods to correlate and understand its adsorptive performance.The characterization data indicate a carbonaceous adsorbent with a specific surface area of 467 m^(2)/g.Zeta potential indicates a material with a negatively charged surface at a pH higher than 3.1,which is extremely beneficial to cations removal.For both rare earths elements(REEs),the adsorption capacity increases with the increase of the pH,reaching its maximum at pH 4-6.The kinetic data are well fitted by Avrami-fractional o rder,while the Liu model agreeably fits equilibrium data.The maximum adsorption capacities for Ce(Ⅲ)and La(Ⅲ)are 48.45 and 53.65 mg/g at 298 K,respectively.The thermodynamic studies suggest that the adsorption process is favorable,spontaneous,and exothermic for both REEs.Pore filling,surface complexation,and ion exchange are the dominant mechanisms.Finally,the VPW-AC was subjected to the recovery of REEs from real phosphogypsum leachate,and it is proved that it can be successfully used to recover REEs in a real process.
文摘The anther-smut Microbotryum violaceum ( Brandenburger and Schvinn) G. Deml. and Oberw.) causes a systematic infection of its host Silene dioica ( L.) Clairv., resulting in sterility and production of teliospores (dispersal propagules) in flowers. These spores are transmitted to healthy plants mainly by flower visitors. The behavioral responses of flower visitors to a variation in floral characters are not only likely to affect rates of pollen export/import, but also the rate of spore deposition and probability of disease. In a transplantation experiment, using plants from four different populations, we tested for correlation between variation in female floral morphology and patterns of spore and pollen deposition, and a resulting risk of disease. The source populations in this experiment were located on four islands in Skeppsvik archipelago in northern Sweden, and represented a gradient of disease incidence from completely healthy ( Island 1), low incidence ( Island 2) to high incidences ( Islands 3 and 4) of disease. Fifty plants from each population were transplanted to the center, of the population on Island 4. There were significant differences among the transplants in floral characters, i.e. corolla size, style length and ovule number. Plants from the non-diseased population had larger flowers and longer styles than plants from the highly diseased populations. Numbers of pollen grains and spores deposited on flowers were strongly and positively correlated. We found that plants originating from the non-diseased population captured approximately 4 times more pollen and 9 times more spores, per flower than die individuals from the resident population (Island 4, population 4). The incidences of disease among plants, from the four populations differed significantly, and was 37%, 20%, 18% and 0 for populations 1, 2, 3 and 4 respectively. In a survey of ten populations we found a significant negative correlation between the mean style length ( positively correlated with corolla size and ovule number) among healthy plants and incidence of disease in these populations. The potentiality for pathogen-pollinator mediated selection oil floral characters; and consequences for gone flow between populations of Silene dioica are discussed.
文摘Dear Editor,Johannes Lehmann and Markus Kleber,in a controversial paper entitled"The contentious nature of soil organic matter"(Lehmann and Kleber,2015),suggested the abandonment of the term"humus"and other associated terms such as"humic","humir","humified","humification".The first reason they cited was that these labels are only instrumental in outdated soil analytical methods,which are based on alkaline extraction of soil organic matter(SOM).
基金the framework of Franco-Algerian cooperation program"Tassili"No.08MDU726
文摘Background: Investigating population ecology of urban bird species,particularly the invasive and expending spe?cies,is the key for the success of urban management and planning strategies.Methods: Populations of two Columbidae species,the Woodpigeon(Columba palumbus) and the Eurasian Collared Dove(Streptopelia decaocto),were monitored from 1992 to 2010 in the Algiers Sahel,the Mitidja Plain and surround?ing areas(Northern Algeria).Monitoring of species densities was performed by the mapping?plot method.The foraging flight routes of Woodpigeon and the distribution of Eurasian Collared Dove were assessed by systematic observations.Results: The number of counted birds was statistically constant at first years of the survey,and then increased sig?nificantly,beginning from low numbers,their densities accelerated sharply between 2001 and 2006,then reached to an equilibrium state.The significant increase in Woodpigeon's population could be explained by the reduced hunt?ing pressure and by species adaptation to new food resources provided by nearby agriculture.Indeed,monitoring of flight directions of the species revealed the use of agricultural landscapes and habitats,which is a good indicator explaining adaptation and trophic niche of the species.The occurrence of the Eurasian Collared Dove in Algiers began in 2000.Its density experienced a rapid increase with similar trend pattern as that of Woodpigeon.Its distributional range is confined mainly in suburban environments of the Mitidja Plain.Conclusion: The modifications of habitats,urbanization increase and the lessening of hunting in the Mitidja Plain facilitated the rapid expansion of the Eurasian Collared Dove and Woodpigeon as well contributed to the increase in their numbers over time.
基金financial support of Chinese Scholarship Council.
文摘Two polymeric complexes, [Cd(BTP)2]n 1 and [Cd(i-BTP)2]n 2, were prepared and investigated by solid 31P and 113Cd NMR spectroscopies. The crystal structure of 2 was determined by X-ray diffraction.
基金This study was supported by the Ministry of Higher Education,Malaysia(FRGS0322-SG-1/2013)Universiti Malaysia Sabah(GUG0521-2/2020).
文摘Objective:To determine the genetic diversity of Plasmodium(P.)knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia,targeting the S-type SSU rRNA gene and including aspects of natural selection and haplotype.Methods:Thirty-nine blood samples infected with P.knowlesi were collected in Sabah,Malaysian Borneo and Peninsular Malaysia.The S-type SSU rRNA gene was amplified using polymerase chain reaction,cloned into a vector,and sequenced.The natural selection and haplotype of the S-type SSU rRNA gene sequences were determined using DnaSP v6 and illustrated using NETWORK v10.This study's 39 S-type SSU rRNA sequences and eight sequences from the Genbank database were subjected to phylogenetic analysis using MEGA 11.Results:Overall,the phylogenetic analysis showed no evidence of a geographical cluster of P.knowlesi isolates from different areas in Malaysia based on the S-type SSU rRNA gene sequences.The S-type SSU rRNA gene sequences were relatively conserved and with a purifying effect.Haplotype sharing of the S-type SSU rRNA gene was observed between the P.knowlesi isolates in Sabah,Malaysian Borneo,but not between Sabah,Malaysian Borneo and Peninsular Malaysia.Conclusions:This study suggests that the S-type SSU rRNA gene of P.knowlesi isolates in Sabah,Malaysian Borneo,and Peninsular Malaysia has fewer polymorphic sites,representing the conservation of the gene.These features make the S-type SSU rRNA gene suitable for comparative studies,such as determining the evolutionary relationships and common ancestry among P.knowlesi species.
文摘Non-equilibrium solidification structures of Cu55Ni45 and Cu55Ni43Co2 alloys were prepared by the molten glass purification cycle superheating method.The variation of the recalescence phenomenon with the degree of undercooling in the rapid solidification process was investigated using an infrared thermometer.The addition of the Co element affected the evolution of the recalescence phenomenon in Cu-Ni alloys.The images of the solid-liquid interface migration during the rapid solidification of supercooled melts were captured by using a high-speed camera.The solidification rate of Cu-Ni alloys,with the addition of Co elements,was explored.Finally,the grain refinement structure with low supercooling was characterised using electron backscatter diffraction(EBSD).The effect of Co on the microstructural evolution during nonequilibrium solidification of Cu-Ni alloys under conditions of small supercooling is investigated by comparing the microstructures of Cu55Ni45 and Cu55Ni43Co2 alloys.The experimental results show that the addition of a small amount of Co weakens the recalescence behaviour of the Cu55Ni45 alloy and significantly reduces the thermal strain in the rapid solidification phase.In the rapid solidification phase,the thermal strain is greatly reduced,and there is a significant increase in the characteristic undercooling degree.Furthermore,the addition of Co and the reduction of Cu not only result in a lower solidification rate of the alloy,but also contribute to the homogenisation of the grain size.