The Wadsley-Roth phase TiNb_(2)O_(7)(TNO)has been identified as a promising anode material with potential for high safety and fast-charging lithium-ion batteries(LIBs),arising from its competitive theoretical specific...The Wadsley-Roth phase TiNb_(2)O_(7)(TNO)has been identified as a promising anode material with potential for high safety and fast-charging lithium-ion batteries(LIBs),arising from its competitive theoretical specific capacity and secure operational potential.Despite the significant advancements in specific capacity,fast charging,and longevity at the coin cell level,a comprehensive understanding and realization of the fast-charging capability and corresponding cycling stability of the TNO under practical application conditions(such as a pouch cell with an anode capacity exceeding 2 mAh cm^(-2))continues to be elusive.In this study,we explore a simple,scalable solid-phase carbon source melt strategy to fabricate the kilogram-level micrometer-scale single-crystal TNO particles enveloped by an ultrathin carbon coating layer of<5 nm(TNO@C).The in-situ X-ray diffraction(XRD)measurement of the LiCoO_(2)‖TNO@C laminated pouch cell(anode mass loading of~10 mg cm^(-2))under fast charging/discharging conditions with the combination of material characterizations and electrochemical analysis reveals a fast,yet stable crystal structure evolution for the micrometer-scale single-crystal TNO@C with only 7.03%fluctuation in unit cell volume value,which is indicative of fast reaction kinetics.The Ah-level laminated LiCoO_(2)‖TNO@C pouch cell achieved 80.8%charge within 6 min(10 C)and retained 85.3%capacity after 1000 cycles at the charging current density of 6 C(10 min),far surpassing all the results in previous publications.The straightforward synthetic approach for the micrometer-scale single-crystal TNO@C,coupled with a clear understanding of reaction kinetics and rapid crystal structure evolution,paves the way for the practical application of the micrometer-scale single-crystal TNO@C anode material for fast charging LIBs.展开更多
In dynamic 5G network environments,user mobility and heterogeneous network topologies pose dual challenges to the effort of improving performance of mobile edge caching.Existing studies often overlook the dynamic natu...In dynamic 5G network environments,user mobility and heterogeneous network topologies pose dual challenges to the effort of improving performance of mobile edge caching.Existing studies often overlook the dynamic nature of user locations and the potential of device-to-device(D2D)cooperative caching,limiting the reduction of transmission latency.To address this issue,this paper proposes a joint optimization scheme for edge caching that integrates user mobility prediction with deep reinforcement learning.First,a Transformer-based geolocation prediction model is designed,leveraging multi-head attention mechanisms to capture correlations in historical user trajectories for accurate future location prediction.Then,within a three-tier heterogeneous network,we formulate a latency minimization problem under a D2D cooperative caching architecture and develop a mobility-aware Deep Q-Network(DQN)caching strategy.This strategy takes predicted location information as state input and dynamically adjusts the content distribution across small base stations(SBSs)andmobile users(MUs)to reduce end-to-end delay inmulti-hop content retrieval.Simulation results show that the proposed DQN-based method outperforms other baseline strategies across variousmetrics,achieving a 17.2%reduction in transmission delay compared to DQNmethods withoutmobility integration,thus validating the effectiveness of the joint optimization of location prediction and caching decisions.展开更多
A simplified CaO-V_(2)O_(5)-MnO_(2) system was established to qualitatively and quantitatively investigate the transformation behavior of vanadates.The results demonstrated dynamic transformations between calcium vana...A simplified CaO-V_(2)O_(5)-MnO_(2) system was established to qualitatively and quantitatively investigate the transformation behavior of vanadates.The results demonstrated dynamic transformations between calcium vanadate and manganese vanadate as n(CaO)/n(V_(2)O_(5))/n(MnO_(2))ratios and roasting temperatures varied.When MnO_(2) was incrementally added with n(CaO)/n(V_(2)O_(5))of 2,some Ca_(2)V_(2)O_(7) converted to Mn_(2)V_(2)O_(7).The mass of vanadium as calcium vanadate consistently exceeded that as manganese vanadate.Conversely,when CaO was gradually added with n(MnO_(2))/n(V_(2)O_(5))of 2,Mn_(2)V_(2)O_(7) tended to transform into Ca_(2)V_(2)O_(7) and Ca3V2O8.The affinity of vanadium for calcium was higher compared that of vanadium for manganese.The specific type of calcium vanadate formed depended on both n(CaO)/n(V_(2)O_(5))/n(MnO_(2))values and roasting temperatures,while manganese vanadate remained predominantly as Mn_(2)V_(2)O_(7).The influence of roasting temperature on the conversion between calcium vanadate and manganese vanadate was minimal.At n(CaO)/n(V_(2)O_(5))/n(MnO_(2))of 2/1/2 and temperatures ranging from 650 to 850°C,the mass ratio of vanadium present as calcium vanadate to manganese vanadate stabilized at approximately 2.展开更多
Precipitation–strengthened high entropy alloys (HEAs) exhibit excellent strength–ductility combinations due to precipitation hindering dislocation gliding and work hardening ability of the matrix. However, the effec...Precipitation–strengthened high entropy alloys (HEAs) exhibit excellent strength–ductility combinations due to precipitation hindering dislocation gliding and work hardening ability of the matrix. However, the effect of compositions on the microstructure and related deformation mechanism of HEAs is still unclear. In this study, we developed two types of L1_(2)–strengthened Al_(5)Ti_(8)Fe_(x)(CoNi)_(86.9–x)B_(0.1) (x = 17, 28) HEAs to study the effect of Fe content on the deformation mechanism. Our results reveal that an increased Fe concentration substantially increases the strength and ductility of Al_(5)Ti_(8)Fe_(x)(CoNi)_(86.9–x)B_(0.1) HEAs at room temperature. For the Al_(5)Ti_(8)Fe17(CoNi)_(69.9)B_(0.1) HEA, the presence of a large amount of ordered L1_(2) phase leads to strain strengthening governed by dynamically refined slip bands. For the Al_(5)Ti_(8)Fe28(CoNi)58.9B_(0.1) HEA, the increasing Fe content raises the stacking fault energy of the matrix and reduces the stability of the FCC matrix, making it less stable than the BCC structure. Additionally, the reduced volume fraction of the ordered L1_(2) precipitated phase and the increased stack fault energy of the FCC matrix lead to an increase in the cross-slip frequency during deformation, which in turn promotes avalanche glide of dislocations on highly stressed crystallographic slip planes and the generation of microbands. The microbands and phase transformation inside the microbands promote the strain strengthening, resulting in enhanced strength and ductility. These findings clarify the effect of the Fe content on the deformation behaviours and provide new insight into the formation mechanism of microbands in precipitation-strengthened HEAs, which will open new avenues for the design of ultra-strong yet ductile alloys in the future.展开更多
Recently, during the investigations on planetary oceans, Hirota-Satsuma-Ito-type models have been developed. In this paper, for a(2+1)-dimensional generalized variable-coefficient Hirota-Satsuma-Ito system describing ...Recently, during the investigations on planetary oceans, Hirota-Satsuma-Ito-type models have been developed. In this paper, for a(2+1)-dimensional generalized variable-coefficient Hirota-Satsuma-Ito system describing the fluid dynamics of shallow-water waves in an open ocean, non-characteristic movable singular manifold and symbolic computation enable an oceanic auto-B?cklund transformation with three sets of the oceanic solitonic solutions. The results rely on the oceanic variable coefficients in that system. Future oceanic observations might detect some nonlinear features predicted in this paper, and relevant oceanographic insights might be expected.展开更多
Manganese ion(Mn^(2+))was generated from metallurgical,steel making and chemical industries.It could affect microbial activity and community structure after entering sewage treatment plant.The effect of Mn^(2+)on the ...Manganese ion(Mn^(2+))was generated from metallurgical,steel making and chemical industries.It could affect microbial activity and community structure after entering sewage treatment plant.The effect of Mn^(2+)on the pollutant removal,metal distribution patterns and composition of microbial communities were investigated in a an anaerobic/anoxic/oxic(A^(2)O)process.The results showed that when Mn^(2+)concentration was 5 mg/L,the efficiencies for the removal of chemical oxygen demand(COD),total nitrogen(TN)and total phosphorus(TP)attained remarkable levels of 96%,93%,and 99%,respectively.In the sludge,the distribution pattern of Mn^(2+)concentration was tightly bound extracellular polymeric substances(TB-EPS)>supernatant>loosely bound EPS(LB-EPS)>soluble microbial products(SMP).Mn^(2+)was found to enrich and accumulate in the microorganism cells.In addition,Mn^(2+)was mainly found in residual fractions and reducible fractions of pellet that manganese was present.The pellet was discovered to contain a substantial quantity of manganese,which was present in various oxidation states,including Mn^(4+),Mn^(3+)and Mn^(2+).The escalating levels of Mn^(2+)led to a reduction in the richness and diversity of microbial communities inhabiting various regions of the A^(2)O reactor.Nonetheless,the uniformity experienced only subtle alterations.Proteobacteria and Bacteroidetes emerged as the leading phyla within the microbial ecosystem,experiencing a steady rise in their respective proportions.The dominant bacterial groups,Azospira and Dechromonas,experienced an incremental increase in their relative prevalence,which played a constructive role in the process of pollutant removal.展开更多
负压波法适合碳捕获、利用与封存(carbon capture utilization and storage,CCUS)技术的CO_(2)管道泄漏定位检测,但超临界CO_(2)管输周边环境及管内高压产生的噪声,影响了定位的准确性。为此,选择小波变换对含噪声的压力信号进行分解降...负压波法适合碳捕获、利用与封存(carbon capture utilization and storage,CCUS)技术的CO_(2)管道泄漏定位检测,但超临界CO_(2)管输周边环境及管内高压产生的噪声,影响了定位的准确性。为此,选择小波变换对含噪声的压力信号进行分解降噪,采用TGNET模拟软件建立CO_(2)管道泄漏模型,通过对比Botros的激波管泄放试验验证了泄漏模型的可行性。使用该泄漏模型对含噪声的压力信号进行小波降噪,再对降噪后的数据进行压差转化和互相关分析,最终得到各组压力传感器接收到压力信号的具体时间差。该泄漏模型还应用到了延长油田360000 t/a超临界CO_(2)管输方案,对人为设定的泄漏口压力噪声进行小波降噪和互相关分析。研究表明,经小波降噪后的压力信号更为稳定、精确,能够得到准确的时间差,为后续负压波法精确定位泄漏点位置提供了依据。展开更多
目的观察火针联合董氏奇穴针刺治疗肩袖损伤的临床疗效及对关节功能及血清前列腺素E_(2)(prostaglandin E_(2),PGE_(2))和转化生长因子-β1(transforming growth factor-β1,TGF-β1)的影响。方法将100例肩袖损伤患者随机分为对照组(50...目的观察火针联合董氏奇穴针刺治疗肩袖损伤的临床疗效及对关节功能及血清前列腺素E_(2)(prostaglandin E_(2),PGE_(2))和转化生长因子-β1(transforming growth factor-β1,TGF-β1)的影响。方法将100例肩袖损伤患者随机分为对照组(50例)和观察组(50例)。对照组予以电针联合董氏奇穴针刺治疗,观察组予以火针联合董氏奇穴针刺治疗。检测视觉模拟量表(visual analog scale,VAS)和美国加利福尼亚大学洛杉矶分校(University of California,Los Angeles,UCLA)肩关节评分、肩关节活动度(range of motion,ROM)及血清PGE_(2)和TGF-β1水平。结果观察组总有效率高于对照组(P<0.05)。治疗后及4周随访时,两组VAS评分及血清PGE_(2)和TGF-β1水平均低于治疗前(P<0.05),且观察组均低于对照组(P<0.05);两组UCLA肩关节评分和肩关节ROM均高于治疗前(P<0.05),且观察组均高于对照组(P<0.05)。4周随访时,两组VAS评分、UCLA肩关节评分、肩关节ROM及血清PGE_(2)和TGF-β1水平与治疗后比较差异无统计系意义(P>0.05)。治疗后血清PGE_(2)、TGF-β1水平与VAS评分呈正相关,与UCLA肩关节评分呈负相关。结论火针和电针联合董氏奇穴针刺治疗肩袖损伤均可缓解疼痛、改善肩关节功能,但火针优于电针,其机制可能与降低血清PGE_(2)和TGF-β1水平有关。展开更多
目的探讨幽门螺杆菌(Hp)阳性早期胃癌患者肿瘤组织中转化生长因子-β_(1)(TGF-β_(1))mRNA、金属基质蛋白酶-2(MMP-2)mRNA、青霉素结合蛋白1A(PBP1A)m RNA表达水平与复发的关系,并分析其对复发的预测价值。方法选取2018年3月至2023年7...目的探讨幽门螺杆菌(Hp)阳性早期胃癌患者肿瘤组织中转化生长因子-β_(1)(TGF-β_(1))mRNA、金属基质蛋白酶-2(MMP-2)mRNA、青霉素结合蛋白1A(PBP1A)m RNA表达水平与复发的关系,并分析其对复发的预测价值。方法选取2018年3月至2023年7月南阳市中心医院收治的214例Hp阳性早期胃癌患者进行前瞻性研究,所有患者均行内镜黏膜下剥离术(ESD),采用实时荧光定量聚合酶链反应(qRT-PCR)法检测肿瘤组织、癌旁组织中TGF-β_(1)m RNA、MMP-2 m RNA、PBP1A m RNA表达水平,并分析其与临床病理特征相关性。依据ESD术后是否复发分为复发组、未复发组,采用q RT-PCR法检测两组患者的TGF-β_(1)m RNA、MMP-2 m RNA、PBP1A m RNA表达水平。采用偏相关性分析肿瘤组织中TGF-β_(1)m RNA、MMP-2 m RNA、PBP1A m RNA表达水平与复发的关系。采用受试者工作特征(ROC)曲线分析TGF-β_(1)m RNA、MMP-2 mRNA、PBP1A m RNA表达水平对复发的预测价值。结果肿瘤组织中TGF-β_(1)mRNA、MMP-2 m RNA表达水平分别为1.04±0.26、1.45±0.31,明显高于癌旁组织的0.85±0.14、1.18±0.25,PBP1A m RNA表达水平为0.31±0.10,明显低于癌旁组织的0.43±0.12,差异均有统计学意义(P<0.05);列联相关系数C分析显示,肿瘤组织中TGF-β_(1)mRNA、MMP-2 m RNA表达水平与临床分期、浸润深度、淋巴结转移呈正相关(P<0.05),与分化程度呈负相关(P<0.05),而PBP1A m RNA表达水平与临床分期、浸润深度、淋巴结转移呈负相关(P<0.05),与分化程度呈正相关(P<0.05);复发组患者的TGF-β_(1)mRNA、MMP-2 m RNA表达水平分别为1.31±0.25、1.74±0.31,明显高于未复发组的1.01±0.20、1.42±0.25,PBP1A mRNA表达水平为0.18±0.05,明显低于未复发组的0.32±0.10,差异均有统计学意义(P<0.05);偏相关性分析显示,肿瘤组织中TGF-β_(1)mRNA、MMP-2m RNA、PBP1A m RNA表达水平与复发显著相关(P<0.05);TGF-β_(1)mRNA、MMP-2 mRNA、PBP1A mRNA单项及联合预测复发的曲线下面积(AUC)分别为0.755、0.742、0.795、0.915,敏感度为75.00%、70.00%、75.00%、80.00%,特异度为72.25%、67.54%、76.95%、95.81%,且预测效能显著高于各指标单独预测价值(Z=2.376、2.413、1.997,P=0.018、0.016、0.046)。结论Hp阳性早期胃癌患者肿瘤组织中TGF-β_(1)m RNA、MMP-2 m RNA表达水平升高,PBP1A m RNA表达水平降低,且与临床病理特征、复发密切相关,联合检测其水平对复发具有较高的预测价值。展开更多
All-solid-state lithium batteries(ASSLBs)based on sulfide electrolytes promise next-generation energy storage with high energy density and safety.However,the sulfide electrolytes suffer from phase instability and slug...All-solid-state lithium batteries(ASSLBs)based on sulfide electrolytes promise next-generation energy storage with high energy density and safety.However,the sulfide electrolytes suffer from phase instability and sluggish interfacial charge transport when pairing with layered oxide cathodes at high voltages.Herein,a simple and efficient strategy is proposed using two-dimensional Ti_(3)C_(2)T_(x)MXene as starting material to in-situ construct a 15 nm Li_(2)TiO_(3) layer on a typical oxide cathode,LiCoO_(2).The in-situ transformation of Ti_(3)C_(2)T_(x)into Li_(2)TiO_(3) layer occurs at a low temperature of 500℃,avoiding the phase deterioration of LiCoO_(2).The thin Li_(2)TiO_(3) layer is Li^(+)conducting and electrochemically stable,thereby preventing the interfacial decomposition of sulfide electrolytes induced by LiCoO_(2) at high voltages and facilitating Li+transport at the interface.Moreover,Li_(2)TiO_(3) can stabilize the layer structure of LiCoO_(2) at high voltages.Consequently,the sulfide-based ASSLB using LiCoO_(2)@Li_(2)TiO_(3) cathode can operate stably at a high voltage of up to 4.5 V(vs.Li+/Li),delivering an outstanding initial specific discharge capacity of 138.8 m Ah/g with a high capacity retention of 86.2% after 100 cycles at 0.2 C.The in-situ transformation strategy may also apply to other MXenes,offering a general approach for constructing other advanced lithiated coatings for oxide cathodes.展开更多
基金support of the Postdoctoral Fellowship Program(Grade B)of China Postdoctoral Science Foundation(No.GZB20240240)the China Postdoctoral Science Foundation(No.2024M751001)。
文摘The Wadsley-Roth phase TiNb_(2)O_(7)(TNO)has been identified as a promising anode material with potential for high safety and fast-charging lithium-ion batteries(LIBs),arising from its competitive theoretical specific capacity and secure operational potential.Despite the significant advancements in specific capacity,fast charging,and longevity at the coin cell level,a comprehensive understanding and realization of the fast-charging capability and corresponding cycling stability of the TNO under practical application conditions(such as a pouch cell with an anode capacity exceeding 2 mAh cm^(-2))continues to be elusive.In this study,we explore a simple,scalable solid-phase carbon source melt strategy to fabricate the kilogram-level micrometer-scale single-crystal TNO particles enveloped by an ultrathin carbon coating layer of<5 nm(TNO@C).The in-situ X-ray diffraction(XRD)measurement of the LiCoO_(2)‖TNO@C laminated pouch cell(anode mass loading of~10 mg cm^(-2))under fast charging/discharging conditions with the combination of material characterizations and electrochemical analysis reveals a fast,yet stable crystal structure evolution for the micrometer-scale single-crystal TNO@C with only 7.03%fluctuation in unit cell volume value,which is indicative of fast reaction kinetics.The Ah-level laminated LiCoO_(2)‖TNO@C pouch cell achieved 80.8%charge within 6 min(10 C)and retained 85.3%capacity after 1000 cycles at the charging current density of 6 C(10 min),far surpassing all the results in previous publications.The straightforward synthetic approach for the micrometer-scale single-crystal TNO@C,coupled with a clear understanding of reaction kinetics and rapid crystal structure evolution,paves the way for the practical application of the micrometer-scale single-crystal TNO@C anode material for fast charging LIBs.
基金supported by the Liaoning Provincial Education Department Fund,grant number JYTZD2023083.
文摘In dynamic 5G network environments,user mobility and heterogeneous network topologies pose dual challenges to the effort of improving performance of mobile edge caching.Existing studies often overlook the dynamic nature of user locations and the potential of device-to-device(D2D)cooperative caching,limiting the reduction of transmission latency.To address this issue,this paper proposes a joint optimization scheme for edge caching that integrates user mobility prediction with deep reinforcement learning.First,a Transformer-based geolocation prediction model is designed,leveraging multi-head attention mechanisms to capture correlations in historical user trajectories for accurate future location prediction.Then,within a three-tier heterogeneous network,we formulate a latency minimization problem under a D2D cooperative caching architecture and develop a mobility-aware Deep Q-Network(DQN)caching strategy.This strategy takes predicted location information as state input and dynamically adjusts the content distribution across small base stations(SBSs)andmobile users(MUs)to reduce end-to-end delay inmulti-hop content retrieval.Simulation results show that the proposed DQN-based method outperforms other baseline strategies across variousmetrics,achieving a 17.2%reduction in transmission delay compared to DQNmethods withoutmobility integration,thus validating the effectiveness of the joint optimization of location prediction and caching decisions.
基金finally supported by the National Natural Science Foundation of China (Nos.52204309,52174277,52374300)。
文摘A simplified CaO-V_(2)O_(5)-MnO_(2) system was established to qualitatively and quantitatively investigate the transformation behavior of vanadates.The results demonstrated dynamic transformations between calcium vanadate and manganese vanadate as n(CaO)/n(V_(2)O_(5))/n(MnO_(2))ratios and roasting temperatures varied.When MnO_(2) was incrementally added with n(CaO)/n(V_(2)O_(5))of 2,some Ca_(2)V_(2)O_(7) converted to Mn_(2)V_(2)O_(7).The mass of vanadium as calcium vanadate consistently exceeded that as manganese vanadate.Conversely,when CaO was gradually added with n(MnO_(2))/n(V_(2)O_(5))of 2,Mn_(2)V_(2)O_(7) tended to transform into Ca_(2)V_(2)O_(7) and Ca3V2O8.The affinity of vanadium for calcium was higher compared that of vanadium for manganese.The specific type of calcium vanadate formed depended on both n(CaO)/n(V_(2)O_(5))/n(MnO_(2))values and roasting temperatures,while manganese vanadate remained predominantly as Mn_(2)V_(2)O_(7).The influence of roasting temperature on the conversion between calcium vanadate and manganese vanadate was minimal.At n(CaO)/n(V_(2)O_(5))/n(MnO_(2))of 2/1/2 and temperatures ranging from 650 to 850°C,the mass ratio of vanadium present as calcium vanadate to manganese vanadate stabilized at approximately 2.
基金supported by the National Key Research and Development Program(No.2022YFB3707103)the Natural Science Foundation of China(No.52174375)+2 种基金the Key Research and Development Program of Shaanxi(No.2022JBGS2-04)the Fund of the State Key Laboratory of Solidification Processing in NWPU(No.2023-TS-13)the Training Program of Innovation and Entrepreneurship for Undergraduates(No.S202310699761).
文摘Precipitation–strengthened high entropy alloys (HEAs) exhibit excellent strength–ductility combinations due to precipitation hindering dislocation gliding and work hardening ability of the matrix. However, the effect of compositions on the microstructure and related deformation mechanism of HEAs is still unclear. In this study, we developed two types of L1_(2)–strengthened Al_(5)Ti_(8)Fe_(x)(CoNi)_(86.9–x)B_(0.1) (x = 17, 28) HEAs to study the effect of Fe content on the deformation mechanism. Our results reveal that an increased Fe concentration substantially increases the strength and ductility of Al_(5)Ti_(8)Fe_(x)(CoNi)_(86.9–x)B_(0.1) HEAs at room temperature. For the Al_(5)Ti_(8)Fe17(CoNi)_(69.9)B_(0.1) HEA, the presence of a large amount of ordered L1_(2) phase leads to strain strengthening governed by dynamically refined slip bands. For the Al_(5)Ti_(8)Fe28(CoNi)58.9B_(0.1) HEA, the increasing Fe content raises the stacking fault energy of the matrix and reduces the stability of the FCC matrix, making it less stable than the BCC structure. Additionally, the reduced volume fraction of the ordered L1_(2) precipitated phase and the increased stack fault energy of the FCC matrix lead to an increase in the cross-slip frequency during deformation, which in turn promotes avalanche glide of dislocations on highly stressed crystallographic slip planes and the generation of microbands. The microbands and phase transformation inside the microbands promote the strain strengthening, resulting in enhanced strength and ductility. These findings clarify the effect of the Fe content on the deformation behaviours and provide new insight into the formation mechanism of microbands in precipitation-strengthened HEAs, which will open new avenues for the design of ultra-strong yet ductile alloys in the future.
基金financially supported by the Scientific Research Foundation of North China University of Technology (Grant Nos.11005136024XN147-87 and 110051360024XN151-86)。
文摘Recently, during the investigations on planetary oceans, Hirota-Satsuma-Ito-type models have been developed. In this paper, for a(2+1)-dimensional generalized variable-coefficient Hirota-Satsuma-Ito system describing the fluid dynamics of shallow-water waves in an open ocean, non-characteristic movable singular manifold and symbolic computation enable an oceanic auto-B?cklund transformation with three sets of the oceanic solitonic solutions. The results rely on the oceanic variable coefficients in that system. Future oceanic observations might detect some nonlinear features predicted in this paper, and relevant oceanographic insights might be expected.
基金supported by Jilin Provincial Department of Education Science and Technology Project(No.JJKH20230152KJ)the Doctoral Research Initiation Fund(No.BSJXM-2022215).
文摘Manganese ion(Mn^(2+))was generated from metallurgical,steel making and chemical industries.It could affect microbial activity and community structure after entering sewage treatment plant.The effect of Mn^(2+)on the pollutant removal,metal distribution patterns and composition of microbial communities were investigated in a an anaerobic/anoxic/oxic(A^(2)O)process.The results showed that when Mn^(2+)concentration was 5 mg/L,the efficiencies for the removal of chemical oxygen demand(COD),total nitrogen(TN)and total phosphorus(TP)attained remarkable levels of 96%,93%,and 99%,respectively.In the sludge,the distribution pattern of Mn^(2+)concentration was tightly bound extracellular polymeric substances(TB-EPS)>supernatant>loosely bound EPS(LB-EPS)>soluble microbial products(SMP).Mn^(2+)was found to enrich and accumulate in the microorganism cells.In addition,Mn^(2+)was mainly found in residual fractions and reducible fractions of pellet that manganese was present.The pellet was discovered to contain a substantial quantity of manganese,which was present in various oxidation states,including Mn^(4+),Mn^(3+)and Mn^(2+).The escalating levels of Mn^(2+)led to a reduction in the richness and diversity of microbial communities inhabiting various regions of the A^(2)O reactor.Nonetheless,the uniformity experienced only subtle alterations.Proteobacteria and Bacteroidetes emerged as the leading phyla within the microbial ecosystem,experiencing a steady rise in their respective proportions.The dominant bacterial groups,Azospira and Dechromonas,experienced an incremental increase in their relative prevalence,which played a constructive role in the process of pollutant removal.
文摘目的观察火针联合董氏奇穴针刺治疗肩袖损伤的临床疗效及对关节功能及血清前列腺素E_(2)(prostaglandin E_(2),PGE_(2))和转化生长因子-β1(transforming growth factor-β1,TGF-β1)的影响。方法将100例肩袖损伤患者随机分为对照组(50例)和观察组(50例)。对照组予以电针联合董氏奇穴针刺治疗,观察组予以火针联合董氏奇穴针刺治疗。检测视觉模拟量表(visual analog scale,VAS)和美国加利福尼亚大学洛杉矶分校(University of California,Los Angeles,UCLA)肩关节评分、肩关节活动度(range of motion,ROM)及血清PGE_(2)和TGF-β1水平。结果观察组总有效率高于对照组(P<0.05)。治疗后及4周随访时,两组VAS评分及血清PGE_(2)和TGF-β1水平均低于治疗前(P<0.05),且观察组均低于对照组(P<0.05);两组UCLA肩关节评分和肩关节ROM均高于治疗前(P<0.05),且观察组均高于对照组(P<0.05)。4周随访时,两组VAS评分、UCLA肩关节评分、肩关节ROM及血清PGE_(2)和TGF-β1水平与治疗后比较差异无统计系意义(P>0.05)。治疗后血清PGE_(2)、TGF-β1水平与VAS评分呈正相关,与UCLA肩关节评分呈负相关。结论火针和电针联合董氏奇穴针刺治疗肩袖损伤均可缓解疼痛、改善肩关节功能,但火针优于电针,其机制可能与降低血清PGE_(2)和TGF-β1水平有关。
文摘目的探讨幽门螺杆菌(Hp)阳性早期胃癌患者肿瘤组织中转化生长因子-β_(1)(TGF-β_(1))mRNA、金属基质蛋白酶-2(MMP-2)mRNA、青霉素结合蛋白1A(PBP1A)m RNA表达水平与复发的关系,并分析其对复发的预测价值。方法选取2018年3月至2023年7月南阳市中心医院收治的214例Hp阳性早期胃癌患者进行前瞻性研究,所有患者均行内镜黏膜下剥离术(ESD),采用实时荧光定量聚合酶链反应(qRT-PCR)法检测肿瘤组织、癌旁组织中TGF-β_(1)m RNA、MMP-2 m RNA、PBP1A m RNA表达水平,并分析其与临床病理特征相关性。依据ESD术后是否复发分为复发组、未复发组,采用q RT-PCR法检测两组患者的TGF-β_(1)m RNA、MMP-2 m RNA、PBP1A m RNA表达水平。采用偏相关性分析肿瘤组织中TGF-β_(1)m RNA、MMP-2 m RNA、PBP1A m RNA表达水平与复发的关系。采用受试者工作特征(ROC)曲线分析TGF-β_(1)m RNA、MMP-2 mRNA、PBP1A m RNA表达水平对复发的预测价值。结果肿瘤组织中TGF-β_(1)mRNA、MMP-2 m RNA表达水平分别为1.04±0.26、1.45±0.31,明显高于癌旁组织的0.85±0.14、1.18±0.25,PBP1A m RNA表达水平为0.31±0.10,明显低于癌旁组织的0.43±0.12,差异均有统计学意义(P<0.05);列联相关系数C分析显示,肿瘤组织中TGF-β_(1)mRNA、MMP-2 m RNA表达水平与临床分期、浸润深度、淋巴结转移呈正相关(P<0.05),与分化程度呈负相关(P<0.05),而PBP1A m RNA表达水平与临床分期、浸润深度、淋巴结转移呈负相关(P<0.05),与分化程度呈正相关(P<0.05);复发组患者的TGF-β_(1)mRNA、MMP-2 m RNA表达水平分别为1.31±0.25、1.74±0.31,明显高于未复发组的1.01±0.20、1.42±0.25,PBP1A mRNA表达水平为0.18±0.05,明显低于未复发组的0.32±0.10,差异均有统计学意义(P<0.05);偏相关性分析显示,肿瘤组织中TGF-β_(1)mRNA、MMP-2m RNA、PBP1A m RNA表达水平与复发显著相关(P<0.05);TGF-β_(1)mRNA、MMP-2 mRNA、PBP1A mRNA单项及联合预测复发的曲线下面积(AUC)分别为0.755、0.742、0.795、0.915,敏感度为75.00%、70.00%、75.00%、80.00%,特异度为72.25%、67.54%、76.95%、95.81%,且预测效能显著高于各指标单独预测价值(Z=2.376、2.413、1.997,P=0.018、0.016、0.046)。结论Hp阳性早期胃癌患者肿瘤组织中TGF-β_(1)m RNA、MMP-2 m RNA表达水平升高,PBP1A m RNA表达水平降低,且与临床病理特征、复发密切相关,联合检测其水平对复发具有较高的预测价值。
基金the financial support from the National Natural Science Foundation of China(Nos.52201242,52250010)Natural Science Foundation of Jiangsu Province(Nos.BK20200386,BK20200186)+1 种基金Young Elite Scientists Sponsorship Program by CAST(No.2021QNRC001)the Fundamental Research Funds for the Central Universities(No.2242022R40018)。
文摘All-solid-state lithium batteries(ASSLBs)based on sulfide electrolytes promise next-generation energy storage with high energy density and safety.However,the sulfide electrolytes suffer from phase instability and sluggish interfacial charge transport when pairing with layered oxide cathodes at high voltages.Herein,a simple and efficient strategy is proposed using two-dimensional Ti_(3)C_(2)T_(x)MXene as starting material to in-situ construct a 15 nm Li_(2)TiO_(3) layer on a typical oxide cathode,LiCoO_(2).The in-situ transformation of Ti_(3)C_(2)T_(x)into Li_(2)TiO_(3) layer occurs at a low temperature of 500℃,avoiding the phase deterioration of LiCoO_(2).The thin Li_(2)TiO_(3) layer is Li^(+)conducting and electrochemically stable,thereby preventing the interfacial decomposition of sulfide electrolytes induced by LiCoO_(2) at high voltages and facilitating Li+transport at the interface.Moreover,Li_(2)TiO_(3) can stabilize the layer structure of LiCoO_(2) at high voltages.Consequently,the sulfide-based ASSLB using LiCoO_(2)@Li_(2)TiO_(3) cathode can operate stably at a high voltage of up to 4.5 V(vs.Li+/Li),delivering an outstanding initial specific discharge capacity of 138.8 m Ah/g with a high capacity retention of 86.2% after 100 cycles at 0.2 C.The in-situ transformation strategy may also apply to other MXenes,offering a general approach for constructing other advanced lithiated coatings for oxide cathodes.
