Recycling and utilization of coal gasification residues for fabricating Fe/C composites as novel microwave absorbents

Under the background of a transformation of the global energy structure,coal gasification technology has a wide application prospect,but its by-product,the coal gasification residue(CGR),is still not being efficiently utilized for recycling.The CGR contains abundant carbon components,which could be applied to the microwave absorption field as the carbon matrix.In this study,Fe/CGR composites are fabricated via a two-step method,including the impregnation of Fe^(3+)and the reduction process.The influence of the different loading capacities of the Fe component on the morphology and electromagnetic properties is studied.Moreover,the loading content of Fe and the surface morphology of the Fe/CGR can be reasonably controlled by adjusting the concentration of the ferric nitrate solution.Meanwhile,Fe particles are evenly inserted on the CGR framework,which expands the Fe/CGR interfaces to enhance interfacial polarization,thus further improving the microwave-absorbing(MA)properties of composites.Particularly,as the Fe^(3+)concentration is 1.0 mol/L,the Fe/CGR composite exhibits outstanding performance.The reflection loss reaches-39.3 dB at 2.5 mm,and the absorption bandwidth covers 4.1 GHz at 1.5 mm.In this study,facile processability,resource recycling,appropriately matched impedance,and excellent MA performance are achieved.Finally,the Fe/CGR composites not only enhance the recycling of the CGR but also pioneer a new path for the synthesis of excellent absorbents.

A Two-Step Crystallization Route for Hierarchical SAPO-34 Molecular Sieves: Unique Structural Features and Catalytic Property for DTO

The hierarchical structure can significantly improve the diffusion efficiency of the catalyst and regulate the product distribution. Therefore, the preparation of hierarchical SAPO-34 molecular sieve has been a hot research topic. With Cetyltrimethyl Ammonium Bromide (CTAB) and Diethylamine (DEA) as templates, a two-step crystallization process was employed to synthesize hierarchical SAPO-34 molecular sieves. We found that the aging process is vital for the formation of pure phase SAPO-34. It was investigated the relationship of crystallinity trend and mesoporous content with the crystallization time. The results showed that the prolongation of crystallization time was beneficial to enhance the crystallinity of the molecular sieve, but unfavourable to the retention of mesoporous structure. The formation process of hierarchical SAPO-34 molecular sieve involved agglomeration, disintegration, crystallization, re-agglomeration and growth. The hierarchical SAPO-34 molecular sieve with a satisfactory crystallinity and considerable mesoporous structure could be obtained after 36 hours of crystallization. Moreover, the sample had the most suitable acid strength as well as acid amount. The catalytic activity was investigated by catalytic dimethyl ether (DME) to olefin (DTO) reaction. It revealed that the conversion of DME and the selectivity to olefins over the hierarchical SAPO-34 molecular sieve were significantly enhanced with comparison to that over microporous SAPO-34 molecular sieve. The amount of coke deposition of the hierarchical SAPO-34 molecular sieve (14.2%) was lower than that over the microporous molecular sieve (16.5%). Meanwhile, the propylene selectivity of hierarchical SAPO-34 was higher than that of microporous SAPO-34 in the whole reaction. In a word, the hierarchical SAPO-34 molecular sieve synthesized in this study showed a longer catalytic life, higher coke deposition resistance and higher propylene selectivity.

B and Fe co-doped Co_(2)P hollow nanocubes for nitrate electroreduction to ammonia

Nitrate(NO_(3)^(−))electroreduction reaction(NO_(3)^(−)RR)provides an attractive and sustainable route for NO_(3)^(−)pollution mitigation or energy-saved ammonia(NH3)synthesis.In this work,high-quality B and Fe co-doped Co_(2) P hollow nanocubes(B/Fe-Co_(2) P HNCs)are successfully synthesized though simultaneous boronation-phosphorization treatment,which reveal outstanding selectivity,activity,stability for the NO_(3)^(−)to NH_(3) conversion in neutral electrolyte because of big surface area,fast mass transport,superhydrophilic surface,and optimized electronic structure.B/Fe-Co_(2) P HNCs can achieve the high NH3 yield rate(22.67 mg h^(−1) mg_(cat)^(−1))as well as Faradaic efficiency(97.54%)for NO_(3)^(−)RR,greatly outperforming most of non-precious metal based NO_(3)^(−)RR electrocatalysts.

Evaluation of groundwater quality in the Xinjiang Plain Area

Groundwater is the main source of drinking water for the urban and rural residents in the plain area of the Xinjiang Uygur Autonomous Region,China.The quality of groundwater has a direct relationship with human health.Thus,386 groundwater samples collected from April to August in 2003 were analyzed.The samples were collected in basic evaluation units which are determined on the basis of watersheds.Total dissolved solids,total hardness,pH value,NH3–N,C6H5OH,Chemiluminescence detection of permanganate index(CODMn)and intestinal germ group were evaluated according to the guidelines of Groundwater Quality Standard(GB/T14848-93).The quality of the groundwater in each evaluation unit was classified by using the One Veto Method(a unified approach stipulated by the Ministry of Water Resources).The results indicate that the groundwater in the mainstream area of the Tarim Basin and the Yerqiang River Sub-basin belongs to Category V;the groundwater in the Wulungu River Sub-basin,the KaiduKongque River Sub-basin,the Kashgar River Sub-basin,the Cherchen River Sub-basin and the Hotan River Subbasin belongs to Category IV;the groundwater in the Aibi Lake System belongs to Category II,and the groundwater of other evaluation units belongs to Category III.The causes of water quality formation were concisely analyzed.The results can be useful for the evaluation and management of water resources in the Xinjiang Plain Area.

Genetic Architecture of Childhood Kidney and Urological Diseases in China

Kidney disease is manifested in a wide variety of phenotypes,many of which have an important hereditary component.To delineate the genotypic and phenotypic spectrum of pediatric nephropathy,a multicenter registration system is being imple-mented based on the Chinese Children Genetic Kidney Disease Database(CCGKDD).In this study,all the patients with kidney and urological diseases were recruited from 2014 to 2020.Genetic analysis was conducted using exome sequencing for families with multiple affected individuals with nephropathy or clinical suspicion of a genetic kidney disease owing to early-onset or extrarenal features.The genetic diagnosis was confirmed in 883 of 2256(39.1%)patients from 23 provinces in China.Phenotypic profiles showed that the primary diagnosis included steroid-resistant nephrotic syndrome(SRNS,23.5%),glomerulonephritis(GN,32.2%),congenital anomalies of the kidney and urinary tract(CAKUT,21.2%),cystic renal disease(3.9%),renal calcinosis/stone(3.6%),tubulopathy(9.7%),and chronic kidney disease of unknown etiology(CKDu,5.8%).The pathogenic variants of 105 monogenetic disorders were identified.Ten distinct genomic disorders were identified as pathogenic copy number variants(CNVs)in 11 patients.The diagnostic yield differed by subgroups,and was highest in those with cystic renal disease(66.3%),followed by tubulopathy(58.4%),GN(57.7%),CKDu(43.5%),SRNS(29.2%),renal calcinosis/stone(29.3%)and CAKUT(8.6%).Reverse phenotyping permitted correct identification in 40 cases with clinical reassessment and unexpected genetic conditions.We present the results of the largest cohort of children with kidney disease in China where diagnostic exome sequencing was performed.Our data demonstrate the utility of family-based exome sequencing,and indicate that the combined analysis of genotype and phenotype based on the national patient registry is pivotal to the genetic diagnosis of kidney disease.