Integrated UV-based photo microreactor-distillation technology toward process intensification of continuous ultra-high-purity electronic-grade silicon tetrachloride manufacture

Ultra-high-purity silicon tetrachloride(SiCl4)is demanded as an electronic-grade chemical to meet the stringent requirements of the rapidly developing semiconductor industry.The high requirement for ultra-high-purity SiCl4 has created the need for a high-efficient process for reducing energy consumption as well as satisfying product quality.In this paper,a mass of production technology of ultra-high-purity SiCl4 was successfully developed through chlorination reaction in the ultraviolet(UV)-based photo microreactor coupled with the distillation process.The influences of key operational parameters,including temperature,pressure,UV wavelength and light intensity on the product quality,especially for hydrogen-containing impurities,were quantified by the infrared transmittance of Fourier transform infrared spectroscopy(FT-IR)at 2185 cm^-1and 2160 cm^-1indicating that chara cteristic vib rational modes of Si-H bonds,as well as the operating conditions of distillation were also investigated as key factors for metal impurities removing.The advanced intensification of SiCl4 manufactured by the integration of photo microreactor and distillation achieves the products with superior specifications higher than the standard commercial products.

Mettl3依赖的m^(6)A甲基化调控CD8^(+)T细胞效应分化和记忆形成

Efficient immune responses rely on the proper differentiation of CD8^(+)T cells into effector and memory cells.Here,we show a critical requirement of N^6-Methyladenosine(m^(6)A)methyltransferase Mettl3 during CD8^(+)T cell responses upon acute viral infection.Conditional deletion of Mettl3 in CD8^(+)T cells impairs effector expansion and terminal differentiation in an m^(6)A-dependent manner,subsequently affecting memory formation and the secondary response of CD8^(+)T cells.Our combined RNA-seq and m^(6)AmiCLIP-seq analyses reveal that Mettl3 deficiency broadly impacts the expression of cell cycle and transcriptional regulators.Remarkably,Mettl3 binds to the Tbx21 transcript and stabilizes it,promoting effector differentiation of CD8^(+)T cells.Moreover,ectopic expression of T-bet partially restores the defects in CD8^(+)T cell differentiation in the absence of Mettl3.Thus,our study highlights the role of Mettl3 in regulating multiple target genes in an m^(6)A-dependent manner and underscores the importance of m^(6)A modification during CD8^(+)T cell response.

Protein crystallization with DNA templates

Protein crystallization plays a significant role in three-dimensional structural analysis and protein pu-rification.It is important to increase the crystallization efficiency,which is possible by adding hetero-geneous templates in crystallization systems.DNA is biologically compatible and artificially designable polymer,which is easy to extract.In this study,single-and double-stranded DNA of precise sequences were designed and used as templates to promote protein crystallization of lysozyme and catalase.In-fluence of DNA,single-stranded DNA with 10,20,40 bases and double-stranded DNA with 10,20,40 base pairs,were investigated.The success rate of obtaining crystals of lysozyme and catalase in equal period was significantly improved with the addition of DNA comparing without templates added.Double-stranded DNA led to higher nucleation rate than that with single-stranded DNA.The promotion of nucleation was more obvious at low concentration of protein solution and with longer chain DNA templates.Crystal number and crystallization rate was enhanced with addition of long double-stranded DNA templates.All the results confirm that DNA is an effective polymer additive to enhance protein crystallization,especially for the application of the scarce protein crystallization.

SRSF1 plays a critical role in invariant natural killer T cell development and function

Invariant natural killer T(iNKT)cells are highly conserved innate-like T lymphocytes that originate from CD4^(+)CD8^(+)double-positive(DP)thymocytes.Here,we report that serine/arginine splicing factor 1(SRSF1)intrinsically regulates iNKT cell development by directly targeting Myb and balancing the abundance of short and long isoforms.Conditional ablation of SRSF1 in DP cells led to a substantially diminished iNKT cell pool due to defects in proliferation,survival,and TCRαrearrangement.The transition from stage 0 to stage 1 of iNKT cells was substantially blocked,and the iNKT2 subset was notably diminished in SRSF1-deficient mice.SRSF1 deficiency resulted in aberrant expression of a series of regulators that are tightly correlated with iNKT cell development and iNKT2 differentiation,including Myb,PLZF,Gata3,ICOS,and CD5.In particular,we found that SRSF1 directly binds and regulates pre-mRNA alternative splicing of Myb and that the expression of the short isoform of Myb is substantially reduced in SRSF1-deficient DP and iNKT cells.Strikingly,ectopic expression of the Myb short isoform partially rectified the defects caused by ablation of SRSF1.Furthermore,we confirmed that the SRSF1-deficient mice exhibited resistance to acute liver injury uponα-GalCer and Con A induction.Our findings thus uncovered a previously unknown role of SRSF1 as an essential post-transcriptional regulator in iNKT cell development and functional differentiation,providing new clinical insights into iNKT-correlated disease.

Enhanced reversibility of the magnetoelastic transition in(Mn,Fe)2(P,Si)alloys via minimizing the transition-induced elastic strain energy

Magnetocaloric materials undergoing reversible phase transitions are highly desirable for magnetic refrigeration applications.(Mn,Fe)_(2)(P,Si)alloys exhibit a giant magnetocaloric effect accompanied by a magnetoelastic transition,while the noticeable irreversibility causes drastic degradation of the magnetocaloric properties during consecutive cooling cycles.In the present work,we performed a comprehensive study on the magnetoelastic transition of the(Mn,Fe)_(2)(P,Si)alloys by high-resolution transmission electron microscopy,in situ field-and temperature-dependent neutron powder diffraction as well as density functional theory calculations(DFT).We found a generalized relationship between the thermal hysteresis and the transition-induced elastic strain energy for the(Mn,Fe)_(2)(P,Si)family.The thermal hysteresis was greatly reduced from 11 to 1 K by a mere 4 at.%substitution of Fe by Mo in the Mn_(1.15)Fe_(0.80)P_(0.45)Si_(0.55)alloy.This reduction is found to be due to a strong reduction in the transition-induced elastic strain energy.The significantly enhanced reversibility of the magnetoelastic transition leads to a remarkable improvement of the reversible magnetocaloric properties,compared to the parent alloy.Based on the DFT calculations and the neutron diffraction experiments,we also elucidated the underlying mechanism of the tunable transition temperature for the(Mn,Fe)_(2)(P,Si)family,which can essentially be attributed to the strong competition between the covalent bonding and the ferromagnetic exchange coupling.The present work provides not only a new strategy to improve the reversibility of a first-order magnetic transition but also essential insight into the electron-spin-lattice coupling in giant magnetocaloric materials.

TCF-1 deficiency influences the composition of intestinal microbiota and enhances susceptibility to colonic inflammation

Dear Editor,The diversity and composition of gut microbiota play critical roles for maintaining the homeostasis of host commensal bacteria which are correlated with mammalian health(Ding and Schloss,2014).Disorder of microbial community is implicated in the pathogenesis of several human diseases,such as autoimmune disease,allergy,diabetes,obesity,and inflammatory bowel disease(IBD),which is clearly demonstrated to relate to gut dysbiosis in patients and mouse models(Saleh and Elson,2011).