In situ formed cross-linked polymer networks as dual-functional layers for high-stable lithium metal batteries

Lithium-metal anodes(LMAs)have been recognized as the ultimate anodes for next-generation batteries with high energy density,but stringent assembly-environment conditions derived from the poor moisture stability dramatically hinder the transformation of LMAs from laboratory to industry.Herein,an in situ formed cross-linked polymer layer on LMAs is designed and constructed by a facile thiol-acrylate click chemistry reaction between poly(ethylene glycol)diacrylate(PEGDA)and the crosslinker containing multi thiol groups under UV irradiation.Owing to the hydrophobic nature of the layer,the treated LMAs demonstrate remarkable humid stability for more than 3 h in ambient air(70%relative humidity).The coating humid-resistant protective layer also possesses a dual-functional characterization as solid polymer electrolytes by introducing lithium bis(trifluoromethanesulfonyl)imide in the system in advance.The intimate contact between the polymer layer and LMAs reduces interfacial resistance in the assembled Li/LiFePO_(4)or Li/LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)full cell effectively,and endows the cell with an outstanding cycle performance.

Synthesis of an IMF zeolite membrane for the separation of xylene isomer

The synthesis of a continuous IMF zeolite membrane was fabricated on tubular substrates by seeded growth for the first time. The straight channels of IMF zeolite with diameters of 0.53–0.59 nm are distinguishable for p-xylene from o-xylene molecules. Pure IMF-phase high-silica IM-5 zeolite seeds with uniform and fine crystal size were fabricated by a new sonication-assisted aging process. The seeds were coated on the support by dipcoating and induced the formation of continuous membrane. Separation performance in p-/o-xylene mixture was investigated at various temperature and pressure. The typical IM-5zeolite membrane had p-/o-xylene separation factor of 3.7. Our results suggest that IM-5 zeolite is a potentially good membrane material for the separation of xylene mixtures.

Eutectic Solution Enables Powerful Click Reaction for In-Situ Construction of Advanced Gel Electrolytes

Thiol-ene click reaction is an intriguing strategy for preparing polymer electrolytes due to its high activity,atom economy and less side reaction.However,the explosive reaction rate and the use of non-electrolytic amine catalyst hamper its application in in-situ batteries.Herein,a nitrogen-containing eutectic solution is designed as both the catalyst of the thiol-ene reaction and the plasticizer to in-situ synthesize the gel polymer electrolytes,realizing a mild in-situ gelation process and the preparation of high-performance gel electrolytes.The obtained gel polymer electrolytes exhibit a high ionic conductivity of 4×10^(−4)S cm^(−1)and lithium-ion transference number(t_(Li)^(+))of 0.51 at 60°C.The as-assembled Li/LiFePO_(4)(LFP)cell delivers a high initial discharge capacity of 155.9 mAh g^(-1),and a favorable cycling stability with the capacity retention of 82%after 800 cycles at 1 C is also obtained.In addition,this eutectic solution significantly improves the rate performance of the LFP cell with high specific capacity of 141.5 and 126.8 mAh g^(-1)at 5 C and 10 C,respectively,and the cell can steadily work at various charge–discharge rate for 200 cycles.This powerful and efficient strategy may provide a novel way for in-situ preparing gel polymer electrolytes with desirable comprehensive performances.

锂离子电池用聚合物隔膜研究进展

锂离子电池具有轻巧、能量密度高、循环寿命长等优点,广泛用于便携式电子设备、电动汽车以及能量存储领域。隔膜作为锂离子电池的关键部件之一,承担着隔离正负极以防止电池短路、为锂离子自由穿梭提供通道的作用,决定了电池的安全性和电化学性能。常用的聚烯烃类隔膜具有良好的力学性能、化学稳定性及低廉的成本,但受自身耐热性差、电解液吸收率与保液率低的限制,难以满足锂离子电池的高安全性和高性能要求。文中从隔膜的制备工艺、表面改性、本征性能以及电化学活化4个方面,阐述了高性能锂离子电池用聚合物隔膜的研究进展,并展望其发展方向。

Characteristics and ozone formation potential of volatile organic compounds in emissions from a typical Chinese coking plant

Coking industry is an important volatile organic compounds(VOCs) emission source in China,however,detailed information on VOCs emissions is lacking.Therefore,we selected a typical mechanized coking plant and collected air samples according to the Emission Standard of Pollutants for Coking Chemical Industry(GB16171-2012).Using gas chromatographymass spectrometry method,we analyzed the VOCs in the air samples,and applied maximum increment reactivity(MIR) rule to estimate ozone formation potential(OFP) of the VOCs emitted from the coke production.More than 90 VOCs species were detected from the coking plant,including alkanes,alkenes,alkynes,aromatic hydrocarbons,halogenated hydrocarbons and oxygenated VOCs.The concentrations of VOCs(p(VOCs)) generated at different stages of the coking process are significantly different.p(VOCs) from coke oven chimney had the highest concentration(87.1 mg/m3),followed by coke pushing(4.0 mg/m3),coal charging(3.3 mg/m3) and coke oven tops(1.1 mg/m3).VOCs species emitted from the coke production processes were dominated by alkanes and alkenes,but the composition proportions were different at the different stages.Alkenes were the most abundant emission species in flue gases of the coke oven chimney accounting for up to 66% of the total VOCs,while the VOCs emissions from coke pushing and coal charging were dominated by alkanes(36% and 42%,respectively),and the alkanes and alkenes emitted from coke oven top were similar(31% and 29%,respectively).Based on above results,reduction of VOCs emissions from coke oven chimney flue gases is suggested to be an effective measure,especially for alkenes.

Ambient volatile organic compounds pollution in China

Owing to rapid economic and industrial development, China has been suffering from degraded air quality and visibility. Volatile organic compounds （VOCs） are important precursors to the formation of ground-level ozone and hence photochemical smog. Some VOCs adversely affect human health. Therefore, VOCs have recently elicited public concern and given new impetus to scientific interest. China is now implementing a series of polices to control VOCs pollution. The key to formulating policy is understanding the ambient VOCs pollution status. This paper mainly analyzes the species, levels, sources, and spatial distributions of VOCs in ambient air. The results show that the concentrations of ambient VOCs in China are much higher than those of developed countries such as the United States and Japan, especial benzene, which exceeds available standards. At the same time, the ozone formation potential （OFP） and secondary organic aerosol formation potential （SOAFP） of various VOCs are calculated. Aromatics and alkenes have much higher OFPs, while aromatics have higher SOAFP. The OFPs of ambient VOCs in the cities of Beijing, Guangzhou and Changchun are very high, and the SOAFP of ambient VOCs in the cities of Hangzhou, Guangzhou and Changchun are higher.

Integrated transcriptome analysis of human iPS cells derived from a fragile X syndrome patient during neuronal differentiation

Fragile X syndrome(FXS) patients carry the expansion of over 200 CGG repeats at the promoter of fragile X mental retardation 1(FMR1), leading to decreased or absent expression of its encoded fragile X mental retardation protein(FMRP). However, the global transcriptional alteration by FMRP deficiency has not been well characterized at single nucleotide resolution, i.e., RNA-seq. Here,we performed in-vitro neuronal differentiation of human induced pluripotent stem(iPS) cells that were derived from fibroblasts of a FXS patient(FXS-iPSC). We then performed RNA-seq and examined the transcriptional misregulation at each intermediate stage during in-vitro differentiation of FXS-iPSC into neurons. After thoroughly analyzing the transcriptomic data and integrating them with those from other platforms, we found up-regulation of many genes encoding TFs for neuronal differentiation(WNT1, BMP4,POU3F4, TFAP2 C, and PAX3), down-regulation of potassium channels(KCNA1, KCNC3, KCNG2, KCNIP4, KCNJ3, KCNK9,and KCNT1) and altered temporal regulation of SHANK1 and NNAT in FXS-iPSC derived neurons, indicating impaired neuronal differentiation and function in FXS patients. In conclusion, we demonstrated that the FMRP deficiency in FXS patients has significant impact on the gene expression patterns during development, which will help to discover potential targeting candidates for the cure of FXS symptoms.

Sinoatrial node pacemaker cells share dominant biological properties with glutamatergic neurons

Activation of the heart normally begins in the sinoatrial node(SAN).Electrical impulses spontaneously released by SAN pacemaker cells(SANPCs)trigger the contraction of the heart.However,the cellular nature of SANPCs remains controversial.Here,we report that SANPCs exhibit glutamatergic neuron-like properties.By comparing the single-cell transcriptome of SANPCs with that of cells from primary visual cortex in mouse,we found that SANPCs co-clustered with cortical neurons.Tissue and cellular imaging confirmed that SANPCs contained key elements of glutamatergic neurotransmitter system,expressing genes encoding glutamate synthesis pathway(G/s),ionotropic and metabotropic glutamate receptors(Grina,Gria3,Grm1 and Grm5)t and glutamate transporters(Slc17a7).SANPCs highly expressed cell markers of glutamatergic neurons(Snap25 and S/-c17a7)t whereas Gad1,a marker of GABAergic neurons,was negative.Functional studies revealed that inhibition of glutamate receptors or transporters reduced spontaneous pacing frequency of isolated SAN tissues and spontaneous Ca2+transients frequency in single SANPC.Collectively,our work suggests that SANPCs share dominant biological properties with glutamatergic neurons,and the glutamatergic neurotransmitter system may act as an intrinsic regulation module of heart rhythm,which provides a potential intervention target for pacemaker cell-associated arrhythmias.

Source,route and effect of Asian sand dust on environment and the oceans

We summarize in this overview achievements in current research frontiers in Asian sand dust with emphasis on the method for sand dust research, the sources of sand dust aerosols, emission of sand dust, mechanism of sand dust weather, chemical transformation during transport, and influences on climatic environment and oceans. Our main results show that most of Asian sand dust comes from Mongolia, the Gobi Desert, arid and semiarid desert areas in northwest China, which is divided into initial sources and enhanced sources. Half of the global production of dust originates from Asian dust source regions. Asian dust weather is so immense that it can cover a 5-？-day journey from the sources to the Korean Peninsula, Japan Islands, and the Pacific Ocean to even impact North America. Asian dust weather plays an active role in the hiogeochemical cycles of trace elements in the mid-latitude Northern Hemisphere.

Single-cell genomics： An overview

The newly developed next-generation sequencing platforms, in combination with gcnome-scale amplification methods, provide a powerful tool to study genomics from a single cell. This mini-review summarizes the technologies of single cell genomics and their applications in several areas of biomedical research including stem cells, cancer biology and reproductive medicine. Particularly, it highlights recent advances in single cell exome sequencing, RNA-seq, and genome sequencing. The application of these powerful techniques will shed new light on the fundamental principles of gene transcription and genome organization at single-cell level and improve our understanding of cellular heterogeneity and diversity in multicellular organisms