Synergistic effects of chemical additives and mature compost on reducing H_2S emission during kitchen waste composting

Additives could improve composting performance and reduce gaseous emission,but few studies have explored the synergistic of additives on H_(2)S emission and compost maturity.This research aims to make an investigation about the effects of chemical additives and mature compost on H_(2)S emission and compost maturity of kitchen waste composting.The results showed that additives increased the germination index value and H_(2)S emission reduction over 15 days and the treatment with both chemical additives and mature compost achieved highest germination index value and H_(2)S emission reduction(85%).Except for the treatment with only chemical additives,the total sulfur content increased during the kitchen waste composting.The proportion of effective sulfur was higher with the addition of chemical additives,compared with other groups.The relative abundance of H_(2)S-formation bacterial(Desulfovibrio)was reduced and the relative abundance of bacterial(Pseudomonas and Paracoccus),which could convert sulfur-containing substances and H_(2)S to sulfate was improved with additives.In the composting process with both chemical additives and mature compost,the relative abundance of Desulfovibrio was lowest,while the relative abundance of Pseudomonas and Paracoccus was highest.Taken together,the chemical additives and mature compost achieved H_(2)S emission reduction by regulating the dynamics of microbial community.

Enhanced organic degradation and microbial community cooperation by inoculating Bacillus licheniformis in low temperature composting

Microbial activity and interaction are the important driving factors in the start-up phase of food waste composting at low temperature.The aim of this study was to explore the effect of inoculating Bacillus licheniformis on the degradation of organic components and the potential microbe-driven mechanism from the aspects of organic matter degradation,enzyme activity,microbial community interaction,and microbial metabolic function.The results showed that after inoculating B.licheniformis,temperature increased to 47.8℃ on day2,and the degradation of readily degraded carbohydrates(RDC)increased by 31.2%,and the bioheat production increased by 16.5%.There was an obvious enhancement of extracellular enzymes activities after inoculation,especially amylase activity,which increased by 7.68 times on day 4.The inoculated B.licheniformis colonized in composting as key genus in the start-up phase.Modular network analysis and Mantel test indicated that inoculation drove the cooperation between microbial network modules who were responsible for various organic components(RDC,lipid,protein,and lignocellulose)degradation in the start-up phase.Metabolic function prediction suggested that carbohydrate metabolisms including starch and sucrose metabolism,glycolysis/gluconeogenesis,pyruvate metabolism,etc.,were improved by increasing the abundance of related functional genes after inoculation.In conclusion,inoculating B.licheniformis accelerated organic degradation by driving the cooperation between microbial network modules and enhancing microbial metabolism in the start-up phase of composting.

Bimetallic CoNiSe_(2)/C nanosphere anodes derived from Ni-Co-metal-organic framework precursor towards higher lithium storage capacity

Through uncomplicated carbonation process,a carbon-embedded CoNiSe_(2)/C nanosphere was synthesized from Ni-Co-MOF (metal-organic framework) precursor whose controllable structure and synergistic effect of bimetallic Ni/Co brought CoNiSe_(2)/C anodes with high specific surface area (172.79 m^(2)/g) and outstanding electrochemical performance.CoNiSe_(2)/C anodes obtained reversible discharge capacities of850.9 mAh/g at 0.1 A/g after cycling for 100 cycles.In addition,CoNiSe_(2)/C exhibits excellent cycle stability and reversibility in the rate test at a current density of 0.1–2.0 A/g.When the current density returns to 0.5 A/g for 150 cycles,its discharge ratio the capacity is 330.8 m Ah/g.Electrochemical impedance spectroscopy (EIS) tests suggested that CoNiSe_(2)/C anodes had a lower charge transfer impedance of 130.02Ωafter 30 cycles.In-situ X-ray diffraction (XRD) tests confirmed the alloying mechanism of CoNiSe_(2)/C which realized higher lithium storage capacity.This work affords substantial evidence for the extension of bimetallic selenides in secondary batteries,promoting the development of bimetallic selenides in anode materials for LIBs.

Review on the recent development of Li_(3)VO_(4)as anode materials for lithium-ion batteries

Among the various anodes,Li_(3)VO_(4)is a potential intercalation kind anode used in lithium-ion batteries(LIBs)that exhibits safer discharge voltage and higher capacity than graphite,a lower voltage plateau than Li_(4)Ti_(5)O_(12),and smaller volume difference in the Li^(+)intercalation/deintercalation process than metals and alloys.However,the comparatively low electronic conductivity,low initial coulombic efficiency(ICE)and serious capacity decay make the Li_(3)VO_(4)anode unviable when it comes to practical implementation.Therefore,this paper reviews the research progress of Li_(3)VO_(4)in recent years,mainly including the strategies of developing different synthesis methods to construct unique morphology,through coating,compositing or elemental doping to increase the ICE,electronic conductivity and the cycle constancy.Moreover,the application of Li_(3)VO_(4)anode materials in other energy storage systems is summarized.Lastly,the development prospect and challenge of Li_(3)VO_(4)anodes are discussed.

Abundance and diversity of candidate division JSl- and Chloroflexi-related bacteria in cold seep sediments of the northern South China Sea

Candidate division JS 1-and Chloroflexi-related bacteria are ubiquitous in various deep marine sediments worldwide, yet almost nothing is known about their abundance and diversity in cold seep sediments. Here, we investigated the abundance and diversity of JS1- and Chloroflexi-related bacteria in a cold seep marine sediment core collected from the northern South China Sea （SCS） with the employment of quantitative polymerase chain reaction （qPCR） and 16S rRNA gene phylogenetic analyses. The qPCR results showed that 16S rRNA gene copies per gram of sediments for the total bacteria and JS 1- and Chloroflexi-related bacteria were at magnitudes of 108 and 106, respectively. The relative abundance of JS 1- and Chloroflexi-related 16S rRNA genes to that of total bacteria was 0.07%-8.78% throughout the core. Phyloge- netic analyses showed that the JS-1 related clone sequences were dominant throughout the core. Our study provided insights into abundance and diversity of JS 1- and Chloroflexi-related bacteria in the northern SCS cold seep sediments.