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Novel nervous and multi-system regenerative therapeutic strategies for diabetes mellitus with mTOR 被引量:14
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作者 Kenneth Maiese 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第3期372-385,共14页
Throughout the globe,diabetes mellitus(DM) is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and af... Throughout the globe,diabetes mellitus(DM) is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and affects all components of the central and peripheral nervous systems that can range from dementia to diabetic neuropathy.The mechanistic target of rapamycin(m TOR) is a promising agent for the development of novel regenerative strategies for the treatment of DM.m TOR and its related signaling pathways impact multiple metabolic parameters that include cellular metabolic homeostasis,insulin resistance,insulin secretion,stem cell proliferation and differentiation,pancreatic β-cell function,and programmed cell death with apoptosis and autophagy.m TOR is central element for the protein complexes m TOR Complex 1(m TORC1) and m TOR Complex 2(m TORC2) and is a critical component for a number of signaling pathways that involve phosphoinositide 3-kinase(PI 3-K),protein kinase B(Akt),AMP activated protein kinase(AMPK),silent mating type information regulation 2 homolog 1(Saccharomyces cerevisiae)(SIRT1),Wnt1 inducible signaling pathway protein 1(WISP1),and growth factors.As a result,m TOR represents an exciting target to offer new clinical avenues for the treatment of DM and the complications of this disease.Future studies directed to elucidate the delicate balance m TOR holds over cellular metabolism and the impact of its broad signaling pathways should foster the translation of these targets into effective clinical regimens for DM. 展开更多
关键词 Akt AMP activated protein kinase(AMPK) apoptosis Alzheimer’s disease autophagy β-cell cancer cardiovascular disease caspase CCN family diabetes mellitus epidermal growth factor erythropoietin fibroblast growth factor forkhead transcription factors Fox o FRAP1 hamartin(tuberous sclerosis 1)/tuberin(tuberous sclerosis 2)(TSC1/TSC2) insulin mechanistic target of rapamycin(mToR) m ToR Complex 1(m T oRC1) m ToR Complex 2(m ToRC2) nicotinamide nicotinamide adenine dinucleotide(NAD+) non-communicable diseases oxidative stress phosphoinositide 3-kinase(PI 3-K) programmed cell death silent mating type information regulation 2 homolog 1(Saccharomyces cerevisiae)(SIRT1) sirtuin stem cells wingless Wnt Wnt1 inducible signaling pathway protein 1(WISP1)
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Influence of Reactive Volatile Organic Compounds on Ozone Production in Houston-Galveston-Brazoria Area
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作者 Samarita Sarker Raghava R. Kommalapati Ziaul Huque 《Journal of Environmental Protection》 2015年第4期399-408,共10页
Secondary pollutant ozone (O3) formation in a particular area is often influenced by various factors. Source of emissions is one of the factors. In south east Texas, Houston-Galveston-Brazoria (HGB) is a marginal non-... Secondary pollutant ozone (O3) formation in a particular area is often influenced by various factors. Source of emissions is one of the factors. In south east Texas, Houston-Galveston-Brazoria (HGB) is a marginal non-attainment area for ozone (O3). A summer episode of May 28 to July 2, 2006 is simulated using Comprehensive Air Quality Model with extensions (CAMx). During this period O3 concentration in HGB often exceeds the National Ambient Air Quality Standards (NAAQS) 0.075 ppm of average 8 hour O3 concentration. HGB area has numerous point sources. Various studies found that some specific volatile organic compounds are very reactive in atmosphere. The objective of this study is to analyze the influence of volatile organic compounds present in point source emissions on the air quality of HGB area. For this purpose ozone sensitivity for HGB area is analyzed by the ratio of hydrogen peroxides (H2O2) to nitric acid (HNO3). HGB area is found NOx limited but reactive VOCs are found to be influential too. From (1-4 June, 2006) maximum O3 concentration was found on weekend, June 3. VOCs such as Acetaldehyde (ALD2), Formaldehyde (FORM) and Alkane (ETHA) showed good correlation with O3 concentrations on that day. In addition, Peroxyacetyl nitrate (PAN) formation was found correlated to higher ozone production. Criteria pollutant Sulfur dioxide (SO2) was found to influence the ALD2 and ETHA concentrations, and thus indirectly influenced O3 production. 展开更多
关键词 Comprehensive Air Quality Model with Extensions (CAMx) Nitrogen oxides (Nox) ozone (o3) VoLATILE organic Compound (VoC) Correlation of VoC with o3
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HPLC特征图谱结合多模式识别及熵权TOPSIS法的不同基原蒲黄药材质量评价 被引量:10
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作者 田芳 张英 +2 位作者 吴孟华 曹晖 马志国 《中草药》 北大核心 2025年第4期1377-1384,共8页
目的建立蒲黄Typhae Pollen的特征图谱分析方法,结合熵权-优劣解距离(TOPSIS)法评价2种基原蒲黄质量,采用化学模式识别分析方法进一步明确2种基原蒲黄的质量差异标志物。方法采用HPLC法建立24批蒲黄不同基原药材的特征图谱,采用“中药... 目的建立蒲黄Typhae Pollen的特征图谱分析方法,结合熵权-优劣解距离(TOPSIS)法评价2种基原蒲黄质量,采用化学模式识别分析方法进一步明确2种基原蒲黄的质量差异标志物。方法采用HPLC法建立24批蒲黄不同基原药材的特征图谱,采用“中药色谱指纹图谱相似度评价系统”软件(2012版)确定2种基原蒲黄各自的共有峰及其基原之间交叉共有峰,均采用对照品进行色谱峰的指认。以峰面积为依据,采用熵权TOPSIS法计算相对贴近程度,得到2种基原蒲黄的综合质量排名及各特征峰的权重;同时,采用主成分分析(principal component analysis,PCA)、偏最小二乘法判别分析(partial least square discriminate analysis,PLS-DA)筛选并确认2种基原蒲黄的质量差异标志物。结果水烛香蒲、东方香蒲特征图谱分别指认并确定了13个特征峰和16个特征峰,其中峰8、9、12是东方香蒲的特有峰,峰7、11与峰13之间的相对峰高可直观区分2种基原蒲黄。特征图谱对比分析发现,东方香蒲的含量测定指标选择峰13(水仙苷)更为合理。熵权TOPSIS法结果表明,各基原蒲黄样品批次间的特征峰均可稳定传递,东方香蒲的相对贴近程度(C_(i))均高于水烛香蒲,说明2种基原蒲黄质量有差异。PCA提取出4个主成分,累积方差贡献率可达89.008%。PLS-DA筛选出山柰酚-3-O-芸香糖苷等9个质量差异标志物,其中山柰酚-3-O-芸香糖苷、异槲皮苷、异鼠李素-3-O-葡萄糖苷等7个质量差异标志物为首次提出。结论建立的分析方法可对2种基原蒲黄进行区分,并特异性识别两者的差异性成分,为蒲黄不同基原之间的区分鉴别及其质量控制提供依据。 展开更多
关键词 水烛香蒲 东方香蒲 特征图谱 熵权ToPSIS法 化学模式识别 质量评价 原儿茶酸 对羟基苯甲酸 香草酸 槲皮素-3-o-(2G-α-L-鼠李糖基)-芸香糖苷 槲皮素-3-o-新橙皮苷 山柰酚-3-o-(2G-α-L-鼠李糖基)-芸香糖苷 香蒲新苷 芦丁 异槲皮苷 山柰酚-3-o-新橙皮苷 异鼠李素-3-o-新橙皮苷 山柰酚-3-o-芸香糖苷 水仙苷 异鼠李素-3-o-葡萄糖苷 柚皮素 异鼠李素
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Metallogenic characteristics and mineralization of supergiant gold deposits(223 t)in the northeastern margin of the Jiaolai Basin,Shandong Province:A review
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作者 Jun-wei Bo Zheng-jiang Ding +3 位作者 Jun Deng Feng-yue Sun Kun-feng Qiu Ming-chun Song 《China Geology》 2025年第4期806-842,共37页
Since the first discovery of gold deposits on the northeastern margin of the Jiaolai Basin in Shandong Province at the end of the 20^(th) century,seven medium-sized to large/super-large gold deposits have been identif... Since the first discovery of gold deposits on the northeastern margin of the Jiaolai Basin in Shandong Province at the end of the 20^(th) century,seven medium-sized to large/super-large gold deposits have been identified in this region,with cumulative proven gold resources of 223 t.This study reviewed the metallogenic and geochemical characteristics of various gold deposits in this region,examined the sources of their ore-forming fluids and materials,as well as their gold metallogenic epochs and processes,and developed a gold metallogenic model.The gold deposits in this region are governed by both dense fractures and detachment structural systems along basin margins,primarily categorized into the altered rock type and the pyrite-bearing carbonate vein type.The latter type,a recently discovered mineralization type in the Jiaodong Peninsula,enjoys high gold grade,a large scale,and high gold mineral fineness,suggesting considerable prospecting potential.Both types of gold deposits show metallogenic epochs ranging from 116 Ma to 119 Ma.Their ore-forming fluids are identified as a CO_(2)-NaCl-H_(2)O fluid system characterized by moderate to low temperatures,moderate to low salinity,and low density,with the pyrite-bearing carbonate vein-type gold deposits manifesting slightly higher salinity.The C-H-O,S,and Pb isotopes of hydrothermal minerals reveal that the ore-forming fluids and materials are characteristic of crust-mantle mixing.Specifically,they were derived from mantle fluids in the early stages,mixed with stratum water and meteoric water in the later stages for mineralization.The gold metallogenic process is identified as follows:During the Early Cretaceous,the subduction of the Pacific Plate and the destruction of the North China Craton led to asthenospheric upwelling.The resulting fluids,after metasomatizing the enriched mantle,differentiated and evolved into C-H-O ore-bearing fluids,which were then mixed with crustal fluids.The mixed fluids migrated to the shallow crust,where they mingled with stratum water and meteoric water.Then,the fluids underwent unloading and final mineralization in detachment fault tectonic systems on basin margins.Due to differences in mixed crustal materials or the surrounding rocks involved in water-rock interactions,altered rock-and pyrite-bearing carbonate vein-type gold deposits were formed in acidic and alkaline fluid environments,respectively. 展开更多
关键词 Supergiant gold deposit Pyrite-bearing carbonate vein-type Altered rock type Co_(2)-NaCl-H_(2)o fluid system C-H-o S and Pbisotopes Mantle fluids Metallogenic characteristics MINERALIZATIoN Mineral exploration engineering Jiaolai Basin Shandong Province
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Syntactic and Socially Responsible Machine Translation:A POS and DEP Integrated Framework for English–Tamil
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作者 Rama Sugavanam Mythili Ramu 《Computers, Materials & Continua》 2026年第4期2302-2326,共25页
When performing English-to-Tamil Neural Machine Translation(NMT),end users face several challenges due to Tamil's rich morphology,free word order,and limited annotated corpora.Although available transformer-based ... When performing English-to-Tamil Neural Machine Translation(NMT),end users face several challenges due to Tamil's rich morphology,free word order,and limited annotated corpora.Although available transformer-based models offer strong baselines,they compromise syntactic awareness and the detection and man-agement of offensive content in cluttered,noisy,and informal text.In this paper,we present POSDEP-Offense-Trans,a multi-task NMT framework that combines Part-of-Speech(POS)and Dependency Parsing(DEP)methods with a robust offensive language classification module.Our architecture enriches the Transformer encoder with syntax-aware embeddings and provides syntax-guided attention mechanisms.The architecture incorporates a structure-aware contrastive loss that reinforces syntactic consistency and deploys auxiliary classification heads for POS tagging,dependency parsing,and multi-class offensive detection.The classifier for offensive words operates at both sentence and token levels and obtains guidance from syntactic features and formal finite automata rules that model offensive language structures-hate speech,profanity,sarcasm,and threats.Using this architecture,we construct a syntactically enriched,socially annotated corpus.Experimental results show improvements in translation quality,with a BLEU score of 33.5,UAS/LAS parsing accuracies of 92.4%and 90%,and a 4.5%Fl-score gain in offensive content detection compared with baseline POS+DEP+Offense models.Also,the proposed model achieved 92.3%in offensive content neutralization,as confirmed by ablation studies.This comprehensive English-Tamil NMT model that unifies syntactic modelling and ethical filtering-laying the groundwork for applications in social media moderation,hate speech mitigation,and policy-compliant multilingual content generation. 展开更多
关键词 PoS-awareNMT dependency parsing syntax-guided attention multi-task learning o.ensive language detection o.ensive language neutralization English–Tamil neural machine translation
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Different effects of eastern and central Pacific El Niño events on the surface shortwave radiation over southern China in winter
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作者 Ming Cheng Ziniu Xiao +4 位作者 Xinyi Lai Jingjing Xu Siyu Lu Baorong Zhou Weisi Deng 《Atmospheric and Oceanic Science Letters》 2026年第1期27-33,共7页
This study investigates the distinct impacts of eastern Pacific(EP)and central Pacific(CP)El Niño events on winter shortwave solar radiation(SSR)in southern China,revealing different spatial distributions and und... This study investigates the distinct impacts of eastern Pacific(EP)and central Pacific(CP)El Niño events on winter shortwave solar radiation(SSR)in southern China,revealing different spatial distributions and underlying mechanisms.The results show that,during the developing winter of EP El Niño,significant SSR reductions occur in southwestern China and the east coast of southern China due to a strong,zonally extended Northwest Pacific anticyclone that transports moisture from the tropical Northwest Pacific and North Indian Ocean,while the northeast of southern China experiences a weak increase in SSR.In contrast,during the developing winter of CP El Niño,SSR decreases in the east of southern China with a significant decrease in the lower basin of the Yangtze River but an increase in the west of southern China with a remarkable increase in eastern Yunnan.The pronounced east-west dipole pattern in SSR anomalies is driven by a meridionally elongated Northwest Pacific anticyclone,which enhances northward moisture transport to the east of southern China while leaving western areas drier.Further research reveals that distinct moisture anomalies during the developing winter of EP and CP events result in divergent SSR distributions across southern China,primarily through modulating the total cloud cover.These findings highlight the critical need to differentiate between El Niño types when predicting medium and long-term variability of radiation in southern China. 展开更多
关键词 EP El Niño CP El Niño Shortwave solar radiation Northwest Pacific anticyclone Total cloud cover Total column water
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Oxygenation promoting Se-coordination of amorphous adjacent Nb-Nb diatomic pairs for high-performance sodium-ion hybrid capacitors
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作者 Wenxiu He Fanyan Zeng +4 位作者 Bowen Liao Qincheng Zheng Dui Ma Meilan Xie Yang Pan 《Journal of Energy Chemistry》 2026年第1期474-483,I0011,共11页
Transition metal selenides as sodium-ion hybrid capacitor(SIHC)anodes still suffer from amorphization difficulties and capacity degradation triggered by polyselenide dissolution.Herein,an atomistic amorphous strategy ... Transition metal selenides as sodium-ion hybrid capacitor(SIHC)anodes still suffer from amorphization difficulties and capacity degradation triggered by polyselenide dissolution.Herein,an atomistic amorphous strategy is proposed to construct adjacent Nb-Nb diatomic pairs with Se/O-coordination(Se4-Nb2-O2)in N-doped carbon-confined amorphous selenide clusters(a-Nb-Se/O@NC).Synergistic carbon confinement and hydrothermal oxygenation induce amorphization of Nb–Se bonds,eliminating crystalline rigidity while creating isotropic dual-ion transport channels and high-density active sites enriched with dangling bonds,thereby enhancing structural integrity and Na+storage capacity.The unique Se/O-coordinated Nb-Nb diatomic configuration establishes an electron-delocalized system,where the low electronegativity of Se counterbalances electron withdrawal from coordinated O at Nb centers.These strengthen d-p orbital hybridization,reduce Na+adsorption energy,and optimize charge transfer pathways and reaction kinetics in the amorphous clusters.Electrochemical tests reveal that the a-Nb-Se/O@NC anode delivers a high reversible capacity of 312.57 mAh g^(−1)and exceptional cyclic stability(103%capacity retention)after 5000 cycles at 10.0 A g^(−1).Assembled SIHCs achieve outstanding energy/power densities(207.1 Wh kg^(−1)/18966 W kg^(−1)),surpassing most amorphous and crystalline counterparts.This work provides methodological insights for the design of electrodes in high-power storage devices through atomic modulation and electronic optimization of amorphous selenides. 展开更多
关键词 Amorphous selenide clusters Adjacent Nb-Nb diatomic pairs Se/o hetero-coordination Microstructural modulation Sodium-ion hybrid capacitors
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Long-term manure amendment enhances N_(2)O emissions from acidic soil by alleviating acidification and increasing nitrogen mineralization
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作者 Lei Wu Jing Hu +4 位作者 Muhammad Shaaban Jun Wang Kailou Liu Minggang Xu Wenju Zhang 《Journal of Integrative Agriculture》 2026年第1期262-272,共11页
Long-term manure application has the potential to alleviate soil acidification, and increase carbon sequestration and nutrient availability, thus improving cropland fertility. However, the mechanisms behind greenhouse... Long-term manure application has the potential to alleviate soil acidification, and increase carbon sequestration and nutrient availability, thus improving cropland fertility. However, the mechanisms behind greenhouse gas N_(2)O emissions from acidic soil mediated by long-term manure application remain poorly understood. Herein, we investigated N_(2)O emission and its linkage with gross N mineralization and nitrification rates, as well as nitrifying and denitrifying microbes in an acidic upland soil subjected to 36-year fertilization treatments, including an unfertilized control(CK), inorganic fertilizer(F), 2× rate of inorganic fertilizer(2F), manure(M), and the combination of inorganic fertilizer and manure(FM) treatments. Compared to the CK treatment(1.34 μg N kg^(-1) d^(-1)), fertilization strongly increased N_(2)O emissions by 34-fold on average, with more pronounced increases in the manure-amendment(10.6-169 μg N kg^(-1) d^(-1)) than those in the inorganic fertilizer treatments(3.26-5.51 μg N kg^(-1) d^(-1)). The manure amendment-stimulated N_(2)O emissions were highly associated with increased soil pH, mean weight diameter of soil aggregates, substrate availability(e.g., particulate organic carbon, NO_(3)^(-)and available phosphorus), gross N mineralization rates, denitrifier abundances and the(nirK+nirS)/nosZ ratio. These findings suggest that the increased N_(2)O emissions primarily resulted from alleviated acidification, increased substrate availability and improved soil structure, thus enhancing microbial N mineralization and favoring N_(2)O^(-)producing denitrifiers over N_(2)O consumers. Moreover, ammonia-oxidizing bacteria(AOB) rather than ammonia-oxidizing archaea(AOA) positively correlated with soil NO_(3)^(-)concentration and N_(2)O emissions, indicating that nitrification indirectly contributed to N_(2)O production by supplying NO_(3)^(-)for denitrification. Collectively, manure amendment potentially stimulates N_(2)O emissions, primarily resulting from alleviated soil acidification and increased substrate availability, thus enhancing N mineralization and denitrifier-mediated N_(2)O production. Our findings suggest that consideration should be given to the greenhouse gas budgets of agricultural ecosystems when applying manure for managing the pH and fertility of acidic soils. 展开更多
关键词 long-term manure amendment N_(2)o emission nitrogen mineralization denitrification (nirK+nirS)/nosZ
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Effect and mechanism of Ti−O solid solution layer on interfacial bonding strength of cold roll bonded titanium/stainless steel laminated composite plate
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作者 Zhi-yan YANG Xue-feng LIU +1 位作者 Hong-ting CHEN Xin MA 《Transactions of Nonferrous Metals Society of China》 2026年第1期171-182,共12页
Titanium plates with a Ti−O solid solution surface-hardened layer were cold roll-bonded with 304 stainless steel plates with high work hardening rates.The evolution and mechanisms affecting the interfacial bonding str... Titanium plates with a Ti−O solid solution surface-hardened layer were cold roll-bonded with 304 stainless steel plates with high work hardening rates.The evolution and mechanisms affecting the interfacial bonding strength in titanium/stainless steel laminated composites were investigated.Results indicate that the hardened layer reduces the interfacial bonding strength from over 261 MPa to less than 204 MPa.During the cold roll-bonding process,the hardened layer fractures,leading to the formation of multi-scale cracks that are difficult for the stainless steel to fill.This not only hinders the development of an interlocking interface but also leads to the presence of numerous microcracks and hardened blocks along the nearly straight interface,consequently weakening the interfacial bonding strength.In metals with high work hardening rates,the conventional approach of enhancing interface interlocking and improving interfacial bonding strength by using a surface-hardened layer becomes less effective. 展开更多
关键词 titanium/stainless steel laminated composite plate Ti−o solid solution hardened layer interlocking interface formation mechanism interfacial bonding strength
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Urea electrosynthesis via an integrated Pd_(1)-Cu interface strategy
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作者 Jiaran Li Ximing Zhang +14 位作者 Siwang Zhang Rongxing Qiu Li Peng Lingzhi Ding Jinlong Wan Baowei Wu Zhixuan Wang Hang Ren Wenjun Tan Jia Yu Shisheng Zheng Jin-Chao Dong Jianfeng Huang Shuliang Yang Jun Li 《Science China Materials》 2026年第3期1590-1599,共10页
Electrocatalytic co-reduction of CO_(2)and nitrate offers an attractive and sustainable pathway for urea synthesis,as it enables the simultaneous valorization of nitrogenous waste and CO_(2)into value-added chemicals.... Electrocatalytic co-reduction of CO_(2)and nitrate offers an attractive and sustainable pathway for urea synthesis,as it enables the simultaneous valorization of nitrogenous waste and CO_(2)into value-added chemicals.However,achieving ambient and high-performance urea electrosynthesis remains a persistent challenge,as it requires the simultaneous activation of CO_(2)and efficient H_(2)O dissociation to supply active^(*)H for^(*)NO x hydrogenation—ultimately forming key Cand N-containing intermediates necessary for effective C-N coupling.The stringent,sequential nature of the reaction requirements continues to present substantial challenges for the rational design of advanced multifunctional catalysts.Herein,we report a creative two-in-one catalyst,bifunctional Pd-single-atom-modified Cu(Pd_(1)Cu)nanorods,to synergistically promote the adsorption and stepwise activation of dual species,that is,CO_(2)and H_(2)O,thereby effectively steering the reaction pathway toward the highly selective synthesis of urea.By integrating experimental evidence,in situ spectroscopy,and computational analyses,we clearly disclose that the atomically dispersed Pd sites kinetically favor the co-generation of^(*)CO and^(*)NH_(2)(via H_(2)O dissociation-driven proton transfer),thereby forming an optimal intermediate balance that facilitates urea synthesis.More importantly,the rationally designed Pd_(1)Cu leverages dual metal active sites to enhance C-N coupling via combined electronic and geometric effects,substantially lowering the reaction energy barrier and improving selectivity toward urea. 展开更多
关键词 NANoMATERIAL NANoCATALYSIS urea electrosynthesis green chemistry H_(2)o dissociation
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Changes in structure and tribological properties of in situ oxygen passivated WS_(2) film after a space exposure experiment outside the Chinese Space Station
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作者 Zhaowang LI Jing ZHOU +8 位作者 Hongyu LV Ke WANG Jun HE Ming HU Jiayi SUN Lijun WENG Longbang GUO Xiaoming GAO Desheng WANG 《Science China(Technological Sciences)》 2026年第3期177-187,共11页
The space environment, particularly highly reactive atomic oxygen(AO), often causes performance degradation and accelerated wear of solid-lubricating materials used in aerospace applications. In this study, an in situ... The space environment, particularly highly reactive atomic oxygen(AO), often causes performance degradation and accelerated wear of solid-lubricating materials used in aerospace applications. In this study, an in situ oxygen-passivated WS_(2) lubricating film(W–S–Ti–O composite film) was deposited to withstand AO irradiation. The structural and tribological evolution of the film was examined after a six-month space exposure experiment conducted outside the Chinese Space Station. The results show that in situ oxygen passivation of sulfur vacancies in the WS_(2) film promoted the formation of a dominant WS_(x)O_(y) phase within the W–S–Ti–O composite film. This phase effectively suppressed excessive WO_(3) formation during prolonged AO exposure while maintaining a low friction coefficient. After space exposure, the film exhibited a low friction coefficient and a wear life exceeding 4.5 × 10^(5) cycles. This performance is attributed to two main factors:(1) the presence of friction-induced spherical WO_(3) nanoparticles(approximately 11 nm) embedded in the transfer film, which promoted a transition from pure sliding to a mixed rolling–sliding regime;and(2) the retention of oriented WS_(2)(002) crystalline layers in the tribofilm, which mitigated the plowing effect of nanoparticles and prevented a significant increase in the wear rate. 展开更多
关键词 solid lubrication W–S–Ti–o film in situ oxygen passivation space exposure
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A Multi-Scale Cross-Band Defense System Integrating Decoupled Visible,Dynamic Infrared Camouflage and Electromagnetic Shielding
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作者 Junlin Liu Shujuan Tan +4 位作者 Xinrui Yang Jiajie Zhu Xin Yan Tianyu Chen Guangbin Ji 《Nano-Micro Letters》 2026年第4期335-352,共18页
Cross-band camouflage technology is a critical necessity,enabling personnel and equipment to evade detection across evolving surveillance systems,thereby enhancing survivability and mission success.Herein,this work de... Cross-band camouflage technology is a critical necessity,enabling personnel and equipment to evade detection across evolving surveillance systems,thereby enhancing survivability and mission success.Herein,this work develops a layer-structured composite system based on carbon nanotube(CNT)film comprising ionic liquid(IL)interlayer for infrared(IR)modulation and surface-engineered Cu_(2)O nanoparticles for visible camouflage.The CNT/IL/CNT architecture enables reversible IR emissivity switching(Δε≈0.55)through electrically driven ion intercalation/deintercalation within 2 s,while spray-coated Cu_(2)O nanoparticles(100~400 nm diameter)on the top CNT film layer generate rich structure colors with 90%IR transmittance.This spectral-decoupling design overcomes the traditional trade-off between color visibility and IR transmittance observed in pigment-based systems.Remarkably,due to physical interface coupling,the Cu_(2)O-coated layer-structured system maintains exceptional electrical conductivity,enabling simultaneous electromagnetic interference shielding and electrothermal energy conversion.The integrated system demonstrates long-term operational stability.By unifying visible-IR camouflage,electromagnetic protection,and energy management in a lightweight platform,this work provides an important paradigm for cross-band camouflage technologies. 展开更多
关键词 Visible camouflage Adaptive IR camouflage Cu_(2)o/CNT composite film Electrothermal energy conversion EMI shielding
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A High-Performance Thermal Charging Cell with High Power Density and Long Runtime Enabled by Zn^(2+)and NH_(4)^(+)Co-insertion
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作者 Zhiwei Han Shengliang Zhang +4 位作者 Helang Huang Jing Wang Hui Dou Tianran Zhang Xiaogang Zhang 《Nano-Micro Letters》 2026年第5期831-845,共15页
Zn-based thermal charging devices,utilizing the synergistic effect of ion thermoextraction and thermodiffusion,are able to efficiently convert thermal energy into electrical energy and storage in the devices,making th... Zn-based thermal charging devices,utilizing the synergistic effect of ion thermoextraction and thermodiffusion,are able to efficiently convert thermal energy into electrical energy and storage in the devices,making them a highly promising technology for low-grade heat recovery and utilization.However,the low output power density and energy conversion efficiency resulted by the slow diffusion kinetics of Zn^(2+)hinder their development.Herein,we present a highperformance thermal charging cell design using Zn^(2+)/NH_(4)^(+)hybrid ion electrolyte,which not only maintains the high output voltage of the Zn-based thermoelectric system,but also significantly enhances the output power density due to the fast diffusion kinetics of NH_(4)^(+).Based on this strategy,the thermal charging cell displays a high thermopower of 12.5 mV K^(-1)and an excellent normalized power density of 19.6 mW m^(-2)K^(-2)at a temperature difference of 35 K.The Carnot-relative efficiency is as high as 12.74%.Moreover,it can operate continuously for over 72 h when the temperature difference persists,achieving a balance between thermoelectric conversion and output.This work provides a simple and effective strategy for the design of high-performance thermal charging cells for low-grade heat conversion and utilization. 展开更多
关键词 Thermal charging cells Zn^(2+)/NH_(4)^(+)hybrid ions Low-grade heat conversion and storage High power density Hydrated V2o5
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Discarded Carbon-Zinc Batteries as Source of an Efficient Heterogeneous Fenton-Like Catalyst Employed to Degrade Organic Molecules in an Aqueous Medium
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作者 A. Valadares S. F. Resende +1 位作者 I. M. F. de Oliveira R. Augusti 《Green and Sustainable Chemistry》 2019年第3期94-103,共10页
The present work evaluates the feasibility of using the raw material collected from discarded zinc-carbon batteries as heterogeneous catalyst to degrade the dye Indigo Carmine in an aqueous solution. Besides the evide... The present work evaluates the feasibility of using the raw material collected from discarded zinc-carbon batteries as heterogeneous catalyst to degrade the dye Indigo Carmine in an aqueous solution. Besides the evident environmental application, this work also presents an economic alternative for the production of new catalysts used to remediate polluted waters. For this, discarded carbon-zinc batteries were gathered, disassembled and their anodic paste collected. After acidic treatment and calcination at 500°C, characterization measurements, i.e. flame atomic absorption spectroscopy (FAAS), nitrogen sorption, X-ray diffraction (XRD) and scanning electron microscopy (SEM), revealed that the so-obtained material consisted mainly of ZnMn2O4. This material acts as a heterogeneous catalyst in a Fenton-like process that degrades the dye Indigo Carmine in water. That is probably due to the presence of Mn(III) (manganese in the +3 oxidation state) in this material that triggers the decomposition of hydrogen peroxide (H2O2) to yield hydroxyl radicals (HO&middot;). Moreover, direct infusion electrospray ionization coupled to high resolution mass spectrometry (ESI-HRMS) was employed to characterize the main by-products resulting from such degradation process. These initial results thus indicate that raw materials from waste batteries can therefore be potentially employed as efficient Fenton-like catalysts to degrade organic pollutants in an aqueous solution. 展开更多
关键词 Electronic Waste Zinc-Carbon BATTERIES ZnMn2o4 FENToN-LIKE Degradation INDIGo CARMINE Direct Infusion ELECTRoSPRAY Ionization High Resolution Mass Spectrometry By-Products Identification
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SIRT1 and stem cells: In the forefront with cardiovascular disease, neurodegeneration and cancer 被引量:11
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作者 Kenneth Maiese 《World Journal of Stem Cells》 SCIE CAS 2015年第2期235-242,共8页
Cardiovascular disease, nervous system disorders, and cancer in association with other diseases such as diabetes mellitus result in greater than sixty percent of the global annual deaths. These noncommunicable disease... Cardiovascular disease, nervous system disorders, and cancer in association with other diseases such as diabetes mellitus result in greater than sixty percent of the global annual deaths. These noncommunicable diseases also affect at least one-third of the population in low and middle-income countries and lead to hypertension, elevated cholesterol, malignancy, and neurodegenerative disorders such as Alzheimer's disease and stroke. With the climbing lifespan of the world's population, increased prevalence of these disorders is expected requiring the development of new therapeutic strategies against these disabling disease entities. Targeting stem cellproliferation for cardiac disease, vascular disorders, cancer, and neurodegenerative disorders is receiving great enthusiasm, especially those that focus upon SIRT1, a mammalian homologue of the yeast silent information regulator-2. Modulation of the cellular activity of SIRT1 can involve oversight by nicotinamide/nicotinic acid mononucleotide adenylyltransferase, mammalian forkhead transcription factors, mechanistic of rapamycin pathways, and cysteine-rich protein 61, connective tissue growth factor, and nephroblastoma over-expressed gene family members that can impact cytoprotective outcomes. Ultimately, the ability of SIRT1 to control the programmed cell death pathways of apoptosis and autophagy can determine not only cardiac, vascular, and neuronal stem cell development and longevity, but also the onset of tumorigenesis and the resistance against chemotherapy. SIRT1 therefore has a critical role and holds exciting prospects for new therapeutic strategies that can offer reparative processes for cardiac, vascular, and nervous system degenerative disorders as well as targeted control of aberrant cell growth during cancer. 展开更多
关键词 Foxo Mechanistic of rapamycin Apoptosis Autophagy Cardiovascular CYSTEINE-RICH protein 61 connective tissue growth factor and nephroblastomaover-expressed gene NEURoDEGENERATIoN Progenitorstem cells SIRT1 CANCER
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Judd–Ofelt analysis of Dy^(3+)doped Ca_(2)MgSi_(2)O_(7) phosphors resulting in white light emission
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作者 Ravi SHRIVASTAVA Nandita M.PRASSANNO +1 位作者 Prachi P.NIMJE Siteshwari CHANDRAKAR 《Optoelectronics Letters》 2025年第12期720-724,共5页
Di-calcium magnesium silicate(Ca_(2)MgSi_(2)O_(7))doped with various concentrations(1.0 mol%,2.0 mol%,2.5 mol%,and 3.0 mol%)of dysprosium(Ⅲ)was prepared using a high-temperature technique named as solid state reactio... Di-calcium magnesium silicate(Ca_(2)MgSi_(2)O_(7))doped with various concentrations(1.0 mol%,2.0 mol%,2.5 mol%,and 3.0 mol%)of dysprosium(Ⅲ)was prepared using a high-temperature technique named as solid state reaction method.The sample with 2.5 mol%of dysprosium(Ⅲ)underwent X-ray diffraction(XRD)characterization to confirm the proper phase formation in the sample.Observed XRD pattern matched significantly with crystallographic open database(Card No.96-210-6180)with a significantly high figure of merit(0.84).Photoluminescence(PL)excitation and emission spectra were also recorded.PL excitation spectrum of Ca_(2)MgSi_(2)O_(7)doped with 2.5 mol%of dysprosium(Ⅲ)exhibited a most prominent peak at 395 nm,therefore,the emission spectra of the samples were monitored at 395 nm excitation.The emission spectra exhibited prominent peaks centered at 483 nm(blue),577 nm(yellow),and 664 nm(orange red)due to the transitions ^(4)F_(9/2)→^(6)H_(15/2),^(4)F_(9/2)→^(6)H_(13/2),and ^(4)F_(9/2)→^(6)H_(11/2),respectively.The Commission Internationale de L’Eclairage(CIE)of this emission spectra was found at(0.304,0.340)which lies in the white light region.Keeping the objective to evaluate the emitted white light for its suitability in light-emitting diode(LED)application,color rendering index(CRI)and color correlated temperature(CCT)were also calculated.Radiation life time was estimated using Judd-Ofelt analysis. 展开更多
关键词 White light emission phase formation Photoluminescence crystallographic open database card X ray diffraction Judd ofelt analysis DYSPRoSIUM Ca MgSi o
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Reactive oxygen species generation by organic materials for efficient photocatalysis
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作者 Qing Liu Tangxin Xiao +1 位作者 Zhouyu Wang Leyong Wang 《Chinese Chemical Letters》 2025年第10期1-3,共3页
Reactive oxygen species(ROS),including singlet oxygen(^(1)O_(2)),hydroxyl radicals(·OH),and superoxide anions(O_(2)^(·-)),are highly reactive molecules that play central roles in many chemical,biological,and... Reactive oxygen species(ROS),including singlet oxygen(^(1)O_(2)),hydroxyl radicals(·OH),and superoxide anions(O_(2)^(·-)),are highly reactive molecules that play central roles in many chemical,biological,and environmental processes due to their strong oxidative power[1].Generating ROS in a controlled manner under mild conditions is essential for achieving selective oxidation reactions.Light-driven methods are especially appealing for this purpose,as they offer precise control over where and when ROS are produced. 展开更多
关键词 superoxide anions o hydroxyl radicals superoxide anions reactive oxygen species singlet oxygen reactive oxygen species ros including selective oxidation reactionslight driven PHoToCATALYSIS
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废弃煤矿巷道CO_(2)“封存-利用”技术探索及转化效率研究
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作者 来兴平 雷彤 +3 位作者 张楠 胡添龙 介凯 刘旭超 《西安科技大学学报》 北大核心 2026年第1期15-26,共12页
为应对全球二氧化碳减排的需求,探索利用废弃煤矿地下空间实现CO_(2)封存与资源化利用的新路径,以提升其环境与资源效益。提出了包含捕集、封存、转化、分离系统的废弃煤矿巷道CO_(2)“封存-利用”一体化技术,基于几何相似理论与固体氧... 为应对全球二氧化碳减排的需求,探索利用废弃煤矿地下空间实现CO_(2)封存与资源化利用的新路径,以提升其环境与资源效益。提出了包含捕集、封存、转化、分离系统的废弃煤矿巷道CO_(2)“封存-利用”一体化技术,基于几何相似理论与固体氧化物电解池(SOEC)技术构建巷道反应硐室与实验室微型反应腔之间尺度映射关系,形成室内试验-井下应用的参数对应体系;通过开展恒电流共电解试验以及气相色谱对气体成分分析,系统揭示反应温度与CO_(2)/H_(2)O气体比例对CO_(2)转化效率的影响。结果表明:在保持A/V不变的条件下,巷道反应硐室尺寸为2.4 m×6 m×3.6 m,对应有效反应面积为384 m^(2);法拉第效率随着温度的升高呈现出“先下降后升高”的特征,随着CO_(2)/H_(2)O气体比例的增加而降低,CO_(2)转化率随着温度升高而显著提升,随着CO_(2)/H_(2)O气体比例增加而降低,在温度为850℃、气体比例CO_(2)∶H_(2)O=1∶1的共电解条件下,CO_(2)实现最优转化效率,转化率达72.22%,法拉第效率为61.77%。研究为实现废弃煤矿巷道CO_(2)封存与高值化利用提供了理论依据与技术支撑。 展开更多
关键词 废弃煤矿 固体氧化物电解池 Co_(2)/H_(2)o共电解 法拉第效率 Co_(2)转化率 相似理论
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Disposal and Treatment Methods for Pesticide Containing Wastewaters: Critical Review and Comparative Analysis 被引量:2
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作者 Mariam T. Al Hattab Abdel E. Ghaly 《Journal of Environmental Protection》 2012年第5期431-453,共23页
Pesticides provide the primary means for controlling organisms that compete with man for food and fibre or cause injury to man, livestock and crops. They played a vital role in the economic production of wide ranges o... Pesticides provide the primary means for controlling organisms that compete with man for food and fibre or cause injury to man, livestock and crops. They played a vital role in the economic production of wide ranges of vegetable, fruit, cereal, forage, fibre and oil crops which now constitute a large part of successful agricultural industry in many countries. After application to the target areas, pesticide residues are removed from applicators by rinsing with water which results in the formation of a toxic wastewater that represents a disposal problem for many farmers. Pesticides can adversely affect people, pets, livestock and wildlife in addition to the pests they are intended to destroy. The phenomenon of biomagnification of some pesticides has resulted in reproductive failure of some fish species and egg shell thinning of birds such as peregrine falcons, sparrow hawk and eagle owls. Pesticide toxicity to humans include skin and eye irritation and skin cancer. Therefore, care must be exercised in the application, disposal and treatment of pesticides. Currently, disposal of pesticide wastewater is carried out by: 1) land cultivation, 2) dumping in soil pits, plastic pits and concrete pits or on land and in extreme cases in streams near the rinsing operation, 3) use of evaporation beds and 4) land filling. These methods of disposal are unsafe as the surface run off will reach streams, rivers and lakes and the infiltration of the wastewater into the local soil will eventually reach ground water. The treatment methods currently used for pesticide wastewater include: 1) incineration (incinerators and open burning), 2) chemical treatments (O3/UV, hydrolysis, Fenton oxidation and KPEG), 3) physical treatments (inorganic, organic absorbents and activated carbon) and 4) biological treatments (composting, bioaugmentation and phytoremediation). Therefore, the choice of safe, on farm disposal techniques for agricultural pesticides is very important. A comparative analysis was performed on 18 methods of pesticide disposal/treatment using six criteria: containment, detoxification ability, cost, time, suitability for on farm use, size and evaporation efficiency. The results indicated that of the 18 methods evaluated, 9 scored above 80/100 and can be used on farm. They were organic absorbents (97), composting (94), bioaugmentation (92), inorganic absorbents (90), Fenton oxidation (86), O3/UV (83), activated carbon (82), hydrolysis (82), and land cultivation (80). The other methods are not suitable for on farm use as they suffered from containment problems, high cost and variability of effectiveness. 展开更多
关键词 Pesticides Health Soil Water DISPoSAL Treatment Land Cultivation DISPoSAL PITS Evaporation PoNDS LANDFILLS Incineration o3/UV Fenton oxidation Hydrolysis Bioremediation Bioaugmentaion
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LiCoO_2梯度包覆LiNi_(0.96)Co_(0.04)O_2电极材料的电化学性能 被引量:5
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作者 顾大明 史鹏飞 +1 位作者 宋振业 张鼎 《无机化学学报》 SCIE CAS CSCD 北大核心 2005年第5期725-728,共4页
LiCoO2 gradient coated LiNi0.96Co0.04O2 material and iso-structure LiNi0.8Co0.2O2 material (the same molar ratio 8/2 of Ni/Co in the two materials) as cathode for lithium-ion batteries were synthesized with a co-preci... LiCoO2 gradient coated LiNi0.96Co0.04O2 material and iso-structure LiNi0.8Co0.2O2 material (the same molar ratio 8/2 of Ni/Co in the two materials) as cathode for lithium-ion batteries were synthesized with a co-precipitation method. Microstructure of iso-structure LiNi0.8Co0.2O2 were about the same as that of LiNiO2, and the structure of the coated material was much more similar to that of LiCoO2 based on the X-ray diffraction patterns. The cycling voltammetry and galvanostatic cycle tests show that the properties of the coated material were improved significantly. The first specific charge and discharge capacity for the coated material was 249.20 mAh·g-1 and 207.90 mAh·g-1 respectively, and the specific discharge capacity for the 100th cycle was still 186.02 mAh·g-1 with an irreversible loss of only 21.1 mAh·g-1. This showed that the new material had a good lithium intercalation-deintrercalation performance. Meanwhile, the mechanism of the sintering reaction was proposed. During the sintering reaction of the precursor with LiOH, the Li+-ion permeated into the body of precursors because the shape of the precursor particles was not changed basically based on scanning electronic microscopy. So, the layer microstructure of the precursor is important for the layer microstructure of lithium nickel cobalt oxides electrode material. 展开更多
关键词 LICoo2 LINI0.8Co0.2o2 电化学性能 电极材料 performa 包覆 梯度 with LINIo2 cobalt the and ratio was first shape more show LioH The met new
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