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HNRNPA2B1-mediated m6A modification enhances lncRNA NORHA stability to control granulosa cell functions 被引量:1
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作者 Chun-Xue Zhou Si-Qi Wang +2 位作者 Ji-Yu Zhang Xing Du Qi-Fa Li 《Zoological Research》 2025年第3期722-732,共11页
NORHA,a long non-coding RNA(lncRNA),serves as a key inducer of follicular atresia in sows by triggering granulosa cells(GCs)apoptosis.However,its regulation by N6-methyladenosine(m6A)-the most abundant RNA modificatio... NORHA,a long non-coding RNA(lncRNA),serves as a key inducer of follicular atresia in sows by triggering granulosa cells(GCs)apoptosis.However,its regulation by N6-methyladenosine(m6A)-the most abundant RNA modification-remains unresolved.This study identified NORHA as a functional target of the m6A reader HNRNPA2B1 in sow GCs(sGCs).Transcriptome-wide mapping of RNA modification sites revealed extensive m6A enrichment on NORHA,with HNRNPA2B1 binding directly to the transcript and enhancing its stability via modification of multiple m6A sites,including A261,A441,and A919.HNRNPA2B1 suppressed 17β-estradiol(E2)biosynthesis and promoted sGC apoptosis by activating the NORHA-FoxO1 axis.FoxO1 subsequently repressed expression of cytochrome P450 family 19 subfamily A member 1(CYP19A1),which encodes the enzyme essential for E2 biosynthesis.Additionally,HNRNPA2B1 functioned as a critical mediator of METTL3-dependent m6A modification,modulating NORHA expression and activity in sGCs.This study highlights an important m6Adependent regulatory mechanism governing NORHA expression in sGCs. 展开更多
关键词 LncRNA NORHA m6A modification HNRNPA2B1 FOXO1 Sow granulosa cells
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疏水改性ZSM-5对双功能催化剂NaFe/ZSM-5催化CO_(2)加氢制绿色航空煤油性能的影响
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作者 薛浩强 李文慧 +2 位作者 刘炳昱 刘民 郭新闻 《低碳化学与化工》 北大核心 2026年第1期16-23,共8页
CO_(2)加氢制绿色航空煤油不仅可以助力实现“碳中和”,也有利于航空业的可持续发展。但CO_(2)为惰性小分子难以活化、C—C耦合定向生成绿色航空煤油组分(C_(8)~C_(16)烃类)难度较高等问题,给催化剂设计带来了较大挑战。采用丙基三甲氧... CO_(2)加氢制绿色航空煤油不仅可以助力实现“碳中和”,也有利于航空业的可持续发展。但CO_(2)为惰性小分子难以活化、C—C耦合定向生成绿色航空煤油组分(C_(8)~C_(16)烃类)难度较高等问题,给催化剂设计带来了较大挑战。采用丙基三甲氧基硅烷(PTMS)对ZSM-5分子筛进行了疏水改性,成功制备了具有不同水接触角的疏水改性ZSM-5分子筛,并将其与NaFe_(3)O_(4)组合构筑了双功能催化剂用于CO_(2)加氢反应。结果表明,丙基三甲氧基硅烷改性不仅能够提高ZSM-5分子筛的疏水性,还可以通过疏水基团对ZSM-5分子筛外表面酸性位点的覆盖作用,抑制长链烃产物在分子筛表面的裂解,提升产物中绿色航空煤油组分选择性。在320℃、3 MPa以及n(H_(2)):n(CO_(2))=3:1反应条件下,NaFe/Z5-0.5PTMS在CO_(2)加氢反应中催化性能最佳,CO_(2)转化率为32.6%,CO选择性仅为9.9%,绿色航空煤油组分选择性为38.8%。 展开更多
关键词 CO_(2)加氢 绿色航空煤油 疏水改性 ZSM-5
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Achieving high capacity and ultra-stable sodium storage of Na_(2)TiV(PO_(4))_(3)cathode by integrated lattice regulation and surface modification 被引量:1
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作者 Lin Zhu Miaomiao Wang +6 位作者 Kang Liang Shuang Xiang Dan Sun Xiaobing Huang Qi Zhang Haiyan Wang Yougen Tang 《Journal of Energy Chemistry》 2025年第4期793-802,共10页
The NASICON-structured Na_(2)VTi(PO_(4))_(3)(NVTPO)has attracted significant attention due to its exceptional structural stability and rapid Na~+mobility.However,the development of this material has been hindered by p... The NASICON-structured Na_(2)VTi(PO_(4))_(3)(NVTPO)has attracted significant attention due to its exceptional structural stability and rapid Na~+mobility.However,the development of this material has been hindered by poor electronic conductivity and inadequate low-temperature performance.Herein,a feasible strategy of lattice regulation integrated with surface modification for NVTPO by nitrogen(N)deep doping is proposed.Systematic characterizations and theoretical calculations confirm that N is doped into both the inner crystal structure of NVTPO and the outer carbon layer.The blueshift of the P—O bonds and charge redistribution induced by the V/Ti—N bonds strengthen the local environment and narrow the bandgap,thereby enabling reversible structural evolution and improving electronic conductivity.As expected,the optimized NVTPO/N@CN material achieves an ultra-high capacity of 188.48 mA h g^(-1)at 10 mA g^(-1)and a long-term lifespan of 2000 cycles at 1 A g^(-1).More importantly,it exhibits competitive low-temperature performance(92.15%retention after 1000 cycles at 300 mA g^(-1)and-15℃)due to reduced charge transfer impedance and activation energy.This deep doping strategy modification is expected to broaden the applications of NASICON-type cathodes. 展开更多
关键词 Sodium-ion batteries Na_(2)VTi(PO_(4))_(3) Dual-strategy modification V/Ti-N bonds Low temperature
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Anchoring oxygen on LiNi_(0.94)Co_(0.05)Mn_(0.01)O_(2)surface by coating Ti_(x)NbB_((1−x))C_(2)boosts long-cycle stability of all-solid-state lithium batteries
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作者 Jingchi Zhang Ze Hua +6 位作者 Ziqi Wu Xinting Cao Wen Yang Ruiwen Shao Yu Bai Zhenhua Wang Kening Sun 《Journal of Energy Chemistry》 2025年第8期183-193,共11页
To satisfy the demands of modern society for high-energy–density sulfide-based all-solid-state lithium batteries(ASSLBs),Ni-rich cathode materials have gained much attention for their high capacity and energy density... To satisfy the demands of modern society for high-energy–density sulfide-based all-solid-state lithium batteries(ASSLBs),Ni-rich cathode materials have gained much attention for their high capacity and energy density.However,their practical deployment is hindered by accelerated interface degradation and capacity decay originating from surface oxygen release and lattice oxygen activation during prolonged cycling.In this study,Ti_(x)NbB_((1−x))C_(2)was successfully coated on the surface of LiNi_(0.94)Co_(0.05)Mn_(0.01)O_(2).Density functional theory(DFT)calculations first elucidate a“point-to-point”anchoring mechanism where each surface oxygen atom coordinates with single species(Ti/Nb/B)offered by Ti_(x)NbB_((1−x))C_(2),which forms robust O–M bonds and sustain a stable interface structure.The electron energy loss spectroscopy(EELS)reveals the segregation of Ti/Nb toward subsurface layers during cycling,creating an optimized lattice oxygen coordination environment and suppressing oxygen activation.The dual oxygen stabilization mechanism dramatically improves the reversibility of phase transition and the structural stability of the Ni-rich cathode materials.Moreover,Ti_(x)NbB_((1−x))C_(2)as the protective layer decreases mechanical strain and suppresses the parasitic reactions.Consequently,the engineered cathode delivers 91%capacity retention after 1000 cycles at 0.3 C,suggesting excellent cycling stability.The research delivers a new design philosophy for the coating layer that can stabilize surface oxygen.Furthermore,the atomistic understanding of the structure–property relationship of the Ni-rich cathode materials provides valuable guidance for the future design of new cathode materials with superior structural stability in ASSLBs. 展开更多
关键词 Ni-rich cathode Ti_(x)nbb_((1−x))C_(2)coating "Point-to-point"anchoring Element segregation All-solid-state lithium batteries Long cycle stability
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Modification of Mg_2Si in Mg-Si alloys with neodymium 被引量:8
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作者 胡继龙 唐昌平 +1 位作者 张新明 邓运来 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第11期3161-3166,共6页
The modification effect of neodymium (Nd) on Mg2Si in the hypereutectic Mg-3%Si (mass fraction) alloy was investigated by optical microcopy, scanning electron microscopy and X-ray diffraction. The results indicate... The modification effect of neodymium (Nd) on Mg2Si in the hypereutectic Mg-3%Si (mass fraction) alloy was investigated by optical microcopy, scanning electron microscopy and X-ray diffraction. The results indicate that the morphology of the primary Mg2Si transforms from coarse dendrite into fine polygon with increasing Nd content. The average size of the primary Mg2Si significantly decreases to about 10 ~ma with increasing Nd content up to 1.0%, and then becomes coarser again. The modification and refinement of the primary Mg2Si are mainly attributed to the poisoning effect. The NdMg2 phase in the primary Mg2Si transforms into NdSi and NdSi2 compounds as the Nd content exceeds 3.0%. Therefore, it is reasonable to conclude that the proper Nd (1.0%) addition can effectively modify and refine the primary Mg2Si. 展开更多
关键词 Mg-Si alloy modification MG2SI ND
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Morphology modification of Mg_2Si by Sr addition in Mg-4%Si alloy 被引量:7
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作者 唐守秋 周吉学 +1 位作者 田长文 杨院生 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第9期1932-1936,共5页
A modification of Mg2Si in the hypereutectic Mg-4%Si alloy(mass fraction) with Sr was investigated.Two types of Mg2Si in the alloys were found:polygonal primary Mg2Si and Chinese script type eutectic Mg2Si.Adding A... A modification of Mg2Si in the hypereutectic Mg-4%Si alloy(mass fraction) with Sr was investigated.Two types of Mg2Si in the alloys were found:polygonal primary Mg2Si and Chinese script type eutectic Mg2Si.Adding Al-10% Sr master alloy to the Mg-4%Si alloy clearly reduced the average size of primary Mg2Si and changed the morphology of eutectic Mg2Si from Chinese script type to polyhedral or fine fibre shape.The refinement of primary Mg2Si is mainly attributed to the heterogeneous nucleation mechanism induced by the Sr-rich particles.The modification of eutectic Mg2Si results from the dissolved Sr,which alters the preferred growth manner of the eutectic. 展开更多
关键词 Mg-Si alloy Al-Sr alloy MG2SI modification REFINEMENT
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Surface modification with SiO_2 coating on biomedical TiNi shape memory alloy by sol-gel method 被引量:1
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作者 杨曙 周非 +4 位作者 肖韬 徐大宝 李周 肖柱 肖自安 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第11期3723-3728,共6页
The effect of heat treatment on the transformation temperature of Ti?52.2%Ni (mole fraction) alloy was studied using differential scanning calorimetry (DSC). The transformation temperatures of the alloy can be adjuste... The effect of heat treatment on the transformation temperature of Ti?52.2%Ni (mole fraction) alloy was studied using differential scanning calorimetry (DSC). The transformation temperatures of the alloy can be adjusted effectively by heat treatment. Dense and stable SiO2 coatings were deposited on the surface of the pre-oxidized TiNi alloy by sol?gel method. The bonding strength of films and matrix was (65.9±1.5) N. The electrochemical corrosion test shows that the TiNi alloy with SiO2 coating has excellent corrosion resistance in the Hank’s simulated body fluid. The release behaviors of Ni ion of the alloy with and without SiO2 coating implanted in the acoustic vesicle of guinea pig were studied by EDS testing, which was inhibited effectively by the dense and stable SiO2 coating on the alloy. 展开更多
关键词 TiNi shape memory alloy surface modification SiO2 coating corrosion resistance BIOCOMPATIBILITY
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B_(2)O_(3)改性剂对含钛高炉渣中黑钛石结晶行为的影响 被引量:1
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作者 杨双平 范博文 +4 位作者 王苗 刘起航 董洁 池延斌 杨尚琦 《中国冶金》 北大核心 2025年第2期114-123,共10页
钒钛磁铁矿是一种综合利用价值极高的复合型矿物,然而高炉冶炼钒钛磁铁矿所产生的含钛高炉渣利用难度较大,导致炉渣的堆积量越来越大。以攀钢高炉渣为原料、B_(2)O_(3)为改性剂,利用高温管式炉进行炉渣高温改性试验,系统研究了B_(2)O_(3... 钒钛磁铁矿是一种综合利用价值极高的复合型矿物,然而高炉冶炼钒钛磁铁矿所产生的含钛高炉渣利用难度较大,导致炉渣的堆积量越来越大。以攀钢高炉渣为原料、B_(2)O_(3)为改性剂,利用高温管式炉进行炉渣高温改性试验,系统研究了B_(2)O_(3)添加量、保温时间、冷却速度3个因素对改性高炉渣中富钛相结晶行为的影响规律,并利用SEM-EDS、X射线衍射对试验的改性高炉渣进行分析。试验结果表明,B_(2)O_(3)改性剂的添加可以显著促使炉渣中的富钛相由钙钛矿向黑钛石转变,富钛相黑钛石在改性渣中以块状和长条状晶体的形式存在,保温时间的延长与冷却速率的减小均有利于改性炉渣中黑钛石晶体的析出、长大。同时,得到黑钛石结晶的最佳工艺参数,即当含钛高炉渣中B_(2)O_(3)添加量(质量分数)为6%,并在1500℃的温度下熔化、再以1℃/min冷却至1300℃并保温90 min时,黑钛石结晶效果最好。该条件下黑钛石的结晶量(体积分数)为26.14%,晶粒尺寸为180.85μm。研究结果对含钛高炉渣的资源利用具有指导意义。 展开更多
关键词 含钛高炉渣 B_(2)O_(3) 富钛相 改性试验 黑钛石 结晶行为 资源利用
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Advances of N-terminal modifications of GLP-1 and their applications for the treatment of type 2 diabetes 被引量:1
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作者 白晓辉 牛有红 +2 位作者 熊德彩 吴艳芬 李云森 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2015年第11期701-711,共11页
Glucagon-like peptide-1(GLP-1) is an endogenous insulinotropic hormone with excellent blood glucose-lowering activity, however, it is rapidly inactivated in the plasma mainly by dipeptidyl peptidase IV(DPP-IV). To... Glucagon-like peptide-1(GLP-1) is an endogenous insulinotropic hormone with excellent blood glucose-lowering activity, however, it is rapidly inactivated in the plasma mainly by dipeptidyl peptidase IV(DPP-IV). To overcome this problem, various N-terminal modifications of GLP-1 have been performed to prolong the in vivo biological activity, by improving the DPP-IV resistance while retaining receptor affinity and receptor activation. These studies have included modifications of His7, Ala8 or Glu9 at the N-terminus of GLP-1 and some other modifications. Among them, Ala8 substitutions with glycine(Gly8) and α-aminoisobutyric acid(Aib8) have been clinically applied in the development of diabetic therapy, such as Exenatide, Semaglutide, Albiglutide and Taspoglutide. In this review, we introduce N-terminal modifications of GLP-1 that have been reported, and discuss their potential and challenges for the treatment of type 2 diabetes. 展开更多
关键词 GLP-1 analogues DPP-IV N-terminal modification Type 2 diabetes
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纳米SiO_(2)在改性沥青中的研究进展
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作者 齐琳 刘斌 +1 位作者 何锐 白浩晨 《应用化工》 北大核心 2025年第10期2714-2722,共9页
综述了单一纳米SiO_(2)改性沥青的制备工艺、常规性能、流变性能、混合料路用性能以及改性机理;其次阐述了纳米SiO_(2)与胶粉、SBS以及其他聚合物(环氧树脂、PE和生物油等)复合改性沥青前后性能变化、并从材料层面分析其主要工作机制,... 综述了单一纳米SiO_(2)改性沥青的制备工艺、常规性能、流变性能、混合料路用性能以及改性机理;其次阐述了纳米SiO_(2)与胶粉、SBS以及其他聚合物(环氧树脂、PE和生物油等)复合改性沥青前后性能变化、并从材料层面分析其主要工作机制,明确其优势和不足之处;最后对纳米SiO_(2)改性沥青的进一步发展方向提出建议,为后续纳米SiO_(2)改性沥青研究方向提供借鉴与指导。 展开更多
关键词 纳米SiO_(2) 改性沥青 流变 改性机理
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ZnFe_(2)O_(4)光催化材料改性及在废水处理中的应用
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作者 安庆锋 李红 《中国陶瓷》 北大核心 2025年第10期1-8,17,共9页
铁酸锌(ZnFe_(2)O_(4))是一种具有广阔应用前景的半导体光催化材料,具有优异的化学稳定性、显著的可见光吸收能力、较小的毒性、良好的磁化性能和成本优势而受到广泛关注。本文综述了ZnFe_(2)O_(4)光催化材料改性的研究进展,探讨了其晶... 铁酸锌(ZnFe_(2)O_(4))是一种具有广阔应用前景的半导体光催化材料,具有优异的化学稳定性、显著的可见光吸收能力、较小的毒性、良好的磁化性能和成本优势而受到广泛关注。本文综述了ZnFe_(2)O_(4)光催化材料改性的研究进展,探讨了其晶体结构和光催化性能。通过掺杂改性、构建异质结、形貌调控和缺陷工程等策略,提高了ZnFe_(2)O_(4)的光吸收性能和电荷分离效率,增强了其光催化活性。此外,阐述了ZnFe_(2)O_(4)光催化材料在废水处理领域的应用,主要包括染料降解、贵金属处理、抗生素降解等方面。最后,对未来的研究方向进行了展望,指出新型改性技术的探索和多种改性技术的结合将是未来研究的重要趋势。 展开更多
关键词 ZnFe_(2)O_(4) 掺杂改性 异质结 废水处理
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粉煤灰多孔材料的制备及其CO_(2)吸附性能研究 被引量:1
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作者 李燕华 《山西化工》 2025年第2期20-22,共3页
以燃煤固废粉煤灰为原料制备多孔材料,并对其进行TEPA(四乙烯五胺)改性,用于CO_(2)吸附性能研究。研究结果表明:溶液的pH值会显著影响多孔材料中介孔的比例,介孔比例高、比表面积和孔体积大的多孔材料适合TEPA改性;TEPA负载量和吸附温... 以燃煤固废粉煤灰为原料制备多孔材料,并对其进行TEPA(四乙烯五胺)改性,用于CO_(2)吸附性能研究。研究结果表明:溶液的pH值会显著影响多孔材料中介孔的比例,介孔比例高、比表面积和孔体积大的多孔材料适合TEPA改性;TEPA负载量和吸附温度会对多孔材料的CO_(2)吸附性能有较大影响,40TEPA/C在70℃下具有最大的CO_(2)吸附容量,为2.96 mmol/g;且40TEPA/C具有较好的循环吸附性能,10次循环后CO_(2)吸附容量仍能达到初始值的92%。 展开更多
关键词 粉煤灰 CO_(2)吸附 胺改性 循环吸附性能
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TiO_(2)基光催化材料的制备、改性和应用研究进展
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作者 陆昆 赵立军 《电镀与精饰》 北大核心 2025年第12期107-116,145,共11页
TiO_(2)基光催化材料在环境净化和生物医学领域展现出巨大潜力,但其本征宽带隙和高载流子复合率严重制约实际应用。从“结构调控-性能优化-应用拓展”的耦合机制视角,系统评述了该领域的最新进展。首先,深入剖析了水热合成法、溶胶-凝... TiO_(2)基光催化材料在环境净化和生物医学领域展现出巨大潜力,但其本征宽带隙和高载流子复合率严重制约实际应用。从“结构调控-性能优化-应用拓展”的耦合机制视角,系统评述了该领域的最新进展。首先,深入剖析了水热合成法、溶胶-凝胶法、等离子喷涂法和磁控溅射等关键制备技术对TiO_(2)材料微观结构的精确调控规律及其对光催化活性、稳定性和可加工性的决定性影响。其次,聚焦于通过离子掺杂、半导体复合及表面修饰等改性策略,系统阐释了电子结构、载流子动力学及表面特性的协同优化机制,揭示了性能增强的物理化学本质。最后,分析了TiO_(2)基光催化功能材料的研究发展趋势,指出其在光催化增效机制、环境治理技术升级和生物医学前沿探索等领域的潜在应用。通过梳理现有成果,为设计高效、智能、多功能的下一代TiO_(2)基光催化材料提供了理论支撑和创新思路,为其推广应用提供参考,旨在进一步推动光催化材料在材料科学的发展。 展开更多
关键词 二氧化钛 光催化 制备方法 改性研究
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Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)包覆LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)正极材料的电化学性能研究
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作者 姚年春 何玉林 +1 位作者 张闽 王自强 《人工晶体学报》 北大核心 2025年第12期2209-2216,共8页
本文采用共沉淀法制备Ni_(0.8)Co_(0.1)Mn_(0.1)O_(2)(OH)_(2)前驱体,通过煅烧制备了LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)正极材料,分别采用1%、2%和3%(质量分数,下同)的Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)对NCM811进行... 本文采用共沉淀法制备Ni_(0.8)Co_(0.1)Mn_(0.1)O_(2)(OH)_(2)前驱体,通过煅烧制备了LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)正极材料,分别采用1%、2%和3%(质量分数,下同)的Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)对NCM811进行包覆改性研究。结果表明:当LATP包覆量为2%时,在3.0~4.3 V条件下循环350次后,容量的保持率为84.65%,而未包覆的NCM811在同样条件下的容量保持率为80.58%。倍率性能测试结果表明,在10 C时,2%LATP样品的放电比容量为117.1 mAh∙g^(-1),未包覆的NCM811样品为101.8 mAh∙g^(-1)。适量的LATP包覆可提高锂离子扩散速率,优化离子传输路径,同时,LATP作为包覆层可以避免正极材料与电解液的直接接触,减少副反应的发生,从而降低界面阻抗,提高循环寿命。 展开更多
关键词 LATP LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) 表面包覆 三元正极材料 高镍 包覆改性
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负载型改性TiO_(2)光催化降解水中布洛芬的研究
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作者 魏婕 巩法涛 王淑晋 《水处理技术》 北大核心 2025年第8期68-76,共9页
以TiO_(2)为光催化剂,玻璃纤维布(GFC)为载体材料,通过溶胶凝胶法及浸渍涂覆法制得Fe、S共掺杂的Fe-S/TiO_(2)/GFC光催化剂。采用SEM、XRD、XPS、UV-vis等手段对其进行分析表征。单因素实验结果表明,当布洛芬溶液初始pH、光照强度、布... 以TiO_(2)为光催化剂,玻璃纤维布(GFC)为载体材料,通过溶胶凝胶法及浸渍涂覆法制得Fe、S共掺杂的Fe-S/TiO_(2)/GFC光催化剂。采用SEM、XRD、XPS、UV-vis等手段对其进行分析表征。单因素实验结果表明,当布洛芬溶液初始pH、光照强度、布洛芬的初始浓度、催化剂的投加量分别为5、54 000 lux、10 mg/L、0.15 g时,布洛芬的降解率最大,分别为80.7%、80.71%、81.64%、82.11%。再通过响应面模型分析得出布洛芬降解的最佳条件为布洛芬溶液pH为5.4、布洛芬溶液初始浓度10.31 mg/L、催化剂的投加量为0.15 g,此时的布洛芬降解率为80.04%。验证实验发现优化后实际响应值与预测的响应值间差距约为0.5%,表明响应面模型具有较好的拟合性,具有可靠性。自然水体中常见的阳离子如Na^(+)、K^(+)、Ca^(2+)和Mg^(2+)对布洛芬的降解过程几乎无影响,常见的阴离子中Cl^(-)和HCO_(3)^(-)对布洛芬的降解有明显的抑制作用,SO42-的影响很小,而NO_(3)^(-)会促进布洛芬的降解。 展开更多
关键词 TiO_(2)光催化剂 铁硫掺杂改性 玻璃纤维布负载 布洛芬
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MODIFICATION OF CeO_2 AND ITS EFFECT ON THE HEAT-RESISTANCE OF SILICONE RUBBER 被引量:6
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作者 申屠宝卿 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2008年第4期489-494,共6页
By means of the wet chemical surface modification,the surface of CeO_2 was modified by vinyltrimethoxysilane (VTMS).Infrared spectroscopy was used to investigate the structure of the modified CeO_2 and the result show... By means of the wet chemical surface modification,the surface of CeO_2 was modified by vinyltrimethoxysilane (VTMS).Infrared spectroscopy was used to investigate the structure of the modified CeO_2 and the result showed that VTMS has been attached onto the surface of CeO_2.Effect of VTMS concentration on the active index of the modified CeO_2 was also studied,and the result indicated that the active index of the modified CeO_2 increases with the increase of VTMS concentration and the optimal concentration o... 展开更多
关键词 Silicone rubber CeO_2 Surface modification HEAT-RESISTANCE
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Effect of Primary and Eutectic Mg_2Si Crystal Modifications on the Mechanical Properties and Sliding Wear Behaviour of an Al–20Mg_2Si–2Cu–xBi Composite 被引量:8
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作者 Saeed Farahany Hamidreza Ghandvar +2 位作者 Nur Azmah Nordin Ali Ourdjini Mohd Hasbullah Idris 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2016年第11期1083-1097,共15页
This work investigated the microstructure evolution, tensile, impact, hardness, and sliding wear properties of an Al–20Mg2Si–2Cu in situ composite treated with different Bi contents. The desired modification of prim... This work investigated the microstructure evolution, tensile, impact, hardness, and sliding wear properties of an Al–20Mg2Si–2Cu in situ composite treated with different Bi contents. The desired modification of primary Mg2 Si particles was achieved with the addition of 0.4 wt% Bi. Increasing Bi beyond 0.4 wt%resulted in a loss of modification, possibly due to the formation of Al8 MgB iS i4 compound before the precipitation of the primary Mg2 Si. Additionally, the structure of the pseudo-eutectic Mg2 Si was transformed from plate to fibrous, which was consistent with decrease of growth temperature extracted from the cooling curve thermal analysis. Addition of Bi had an effect on the morphology of Al5 Fe Si(β), Al2Cu(θ) and Al5Cu2Mg8Si6(Q) intermetallic compounds. The tensile strength, elongation percentage, impact toughness, and hardness increased by 6%, 13%, 75%, and 23%, respectively, due to modification of both the primary and eutectic Mg2 Si crystals. The tensile and impact fracture surfaces showed fewer decohered particles in the Bi-treated composite. The enhancement in wear resistance of the Bi-treated composite could be attributed to solid lubricant function of insoluble soft Bi phase and modification effects on Mg2 Si particles. 展开更多
关键词 Al–Mg2Si COMPOSITE modification Bismuth Mechanical properties Wear
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Modification effect of lanthanum on primary phase Mg_2Si in Mg-Si alloys 被引量:6
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作者 王丽萍 郭二军 马宝霞 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第1期105-109,共5页
The modifying effect of La addition on primary phase Mg2Si in Mg-5Si alloys was investigated. The results showed that a proper amount of La could effectively modify the primary phase Mg2Si, Based on the present experi... The modifying effect of La addition on primary phase Mg2Si in Mg-5Si alloys was investigated. The results showed that a proper amount of La could effectively modify the primary phase Mg2Si, Based on the present experiment, the optimal modification effect was obtained with an addition of about 0.5 wt.% La. The size of the primary phase MgzSi was considerably reduced to 25μm or less and the morphology was modified from a coarse dendritic shape to a polyhedral shape. However, when the addition of La increased to 0.8 wt.% or higher, the primary Mg2Si grew into a coarse dendritic morphology again. Moreover, it was found that some LaSi2 compounds were formed during solidification and the amount of the compounds appeared to increase gradually with increasing La content. 展开更多
关键词 modification MAGNESIUM inicrostructure MG2SI La rare earths
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Post-translational modifications of prostaglandin-endoperoxide synthase 2 in colorectal cancer:An update 被引量:8
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作者 Rafael I Jaén Patricia Prieto +2 位作者 Marta Casado Paloma Martín-Sanz Lisardo Boscá 《World Journal of Gastroenterology》 SCIE CAS 2018年第48期5454-5461,共8页
The biosynthesis of prostanoids is involved in both physiological and pathological processes.The expression of prostaglandin-endoperoxide synthase 2(PTGS2;also known as COX-2)has been traditionally associated to the o... The biosynthesis of prostanoids is involved in both physiological and pathological processes.The expression of prostaglandin-endoperoxide synthase 2(PTGS2;also known as COX-2)has been traditionally associated to the onset of several pathologies,from inflammation to cardiovascular,gastrointestinal and oncologic events.For this reason,the search of selective PTGS2 inhibitors has been a focus for therapeutic interventions.In addition to the classic non-steroidal anti-inflammatory drugs,selective and specific PTGS2 inhibitors,termed coxibs,have been generated and widely used.PTGS2 activity is less restrictive in terms of substrate specificity than the homeostatic counterpart PTGS1,and it accounts for the elevated prostanoid synthesis that accompanies several pathologies.The main regulation of PTGS2 occurs at the transcription level.In addition to this,the stability of the mRNA is finely regulated through the interaction with several cytoplasmic elements,ranging from specificmicroR NAs to proteins that control mR NA degradation.Moreover,the protein has been recognized to be the substrate for several post-translational modifications that affect both the enzyme activity and the targeting for degradation via proteasomal and non-proteasomal mechanisms.Among these modifications,phosphorylation,glycosylation and covalent modifications by reactive lipidic intermediates and by free radicals associated to the proinflammatory condition appear to be the main changes.Identification of these post-translational modifications is relevant to better understand the role of PTGS2 in several pathologies and to establish a correct analysis of the potential function of this protein in diseases progress.Finally,these modifications can be used as biomarkers to establish correlations with other parameters,including the immunomodulation dependent on molecular pathological epidemiology determinants,which may provide a better frame for potential therapeutic interventions. 展开更多
关键词 PROSTAGLANDINS Prostaglandin-endoperoxide synthase 2 Post-translational modifications GLYCOSYLATION Colorectal cancer INFLAMMATION
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Effect of Al2O3 modification on enrichment and stabilization of chromium in stainless steel slag 被引量:8
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作者 Long-hu Cao Cheng-jun Liu +1 位作者 Qing Zhao Mao-fa Jiang 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2017年第3期258-265,共8页
Spinel phase is considered to be the optimal phase for stabilization of chromium in stainless steel slag.In order to restrain chromium leaching from slag for the effective environmental protection,Al2O3 was utilized f... Spinel phase is considered to be the optimal phase for stabilization of chromium in stainless steel slag.In order to restrain chromium leaching from slag for the effective environmental protection,Al2O3 was utilized for the modification treatment,and the effects on the enrichment and stabilization of chromium were investigated. The mineral phases and the existence state of chromium in slag with various Al2O3 contents at different basicities( w(CaO)/w(SiO2) were analyzed by scanning electron microscopy-energy dispersive spectroscopy( SEM-EDS) and X-ray diffraction( XRD). The results showed that chromium mainly existed in the glass and spinel phases at basicity of 1. 0 and 1. 5. As the slag basicity increased to 2. 0,chromium was also found in periclase phase. Al2O3 in the stainless steel slag reacted with MgO and Cr2O3,which could generate the Al-rich Mg(CrxAl(1- x))2O4 solid solution. Moreover,the addition of Al2O3 was favorable to reduce the solubility of chromium oxide in liquid phase and suppress the precipitation of periclase phase. The experimental results demonstrated that Al2O3 modification has a positive influence on the enrichment and the stabilization of chromium in the stainless steel slag. 展开更多
关键词 Stainless steel slag CHROMIUM SPINEL Al2O3 modification ENRICHMENT STABILIZATION
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