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Optimizing electrochemical microenvironment of Ni sites by constructing Ni–WO_(2)heterostructure for promoting electrocatalytic conversion of methanol to formate via direct electrooxidation path
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作者 Shuai He Man Zhao +9 位作者 Peipei Zhao Jiamin Ma Chunmei Liu He Xiao Li Zhang Junming Zhang Tianjun Hu Shengxiang Wang Huan Pang Jianfeng Jia 《Rare Metals》 2025年第11期8593-8608,共16页
Nickel-based catalysts display promising potential in integrated hydrogen production through methanol electrooxidation(MOR).The unavoidable selfoxidation from Ni(OH)_(2)to NiOOH severely restricts their MOR performanc... Nickel-based catalysts display promising potential in integrated hydrogen production through methanol electrooxidation(MOR).The unavoidable selfoxidation from Ni(OH)_(2)to NiOOH severely restricts their MOR performance.To inspire the progress of MOR before self-oxidation of Ni species by altering reaction pathways,a heterostructured Ni-WO_(2)catalyst is constructed to follow the direct electrooxidation pathway of methanol.Insitu/ex-situ characterization techniques combined with density functional theory calculations reveal the constructed Ni-WO_(2)hetero structure alters the electronic structure of Ni site.It's found Ni-Ni bond in Ni-WO_(2)becomes longer and the electrons transfer from Ni sites to W sites.This results in up shifted d band center of Ni site and its closing to the Fermi energy level,which optimizes the CH_(3)OH adsorption and the deprotonation of*CH_(3)O into*CH_(2)O in potential-determining step.Moreover,the formed asymmetric adsorption sites increase the polarity of the methanol and the intermediate.As expected,CH_(3)OH molecule is highly converted into HCOOH via direct electrooxidation pathway.This obtained Ni-WO_(2)exhibits superior MOR activity with high peak current density of 325.26 mA cm^(-2) and performs long term of 90 h at10 mA cm^(-2) in hydrogen production.This work provides an important guidance for designing efficient Ni-based samples for direct electrooxidation of methanol. 展开更多
关键词 Methanol electrooxidation reaction Heterojunction structure Direct electrooxidation path Ni-WO_(2)catalyst Electrochemical microenvironment
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淫羊藿苷延缓衰老过程中对ATM-Chk2-p53通路的调节作用 被引量:5
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作者 陈晓亮 张素琴 《老年医学与保健》 CAS 2016年第6期341-344,共4页
目的观察淫羊藿苷对老年小鼠DNA损伤检验点ATM-Chk2-p53通路的调节作用。方法 21月龄C57BL/6老年小鼠随机分为老年对照组和淫羊藿苷组,同时取3月龄小鼠作为青年对照组;淫羊藿苷组小鼠给予含0.02%淫羊藿苷的饲料喂养,老年对照组和青年对... 目的观察淫羊藿苷对老年小鼠DNA损伤检验点ATM-Chk2-p53通路的调节作用。方法 21月龄C57BL/6老年小鼠随机分为老年对照组和淫羊藿苷组,同时取3月龄小鼠作为青年对照组;淫羊藿苷组小鼠给予含0.02%淫羊藿苷的饲料喂养,老年对照组和青年对照组小鼠给予普通正常小鼠饲料喂养。利用淫羊藿苷干预3个月后,在实验之前部分小鼠先进行5Gy X线照射6 h,然后所有小鼠麻醉后处死,收集标本进行相关实验。取小鼠脾脏,抽提小鼠脾组织中的总RNA,利用Real-time PCR方法检测DNA损伤检验点上关键分子ATM、Chk2和p53的mRNA表达水平;提取小鼠脾组织中的总蛋白,采用Western blot方法检测DNA损伤检验点上p-ATM、p-Chk2和p-p53蛋白的表达。结果在电离辐射情况下,老年小鼠ATM、Chk2和p53基因的mRNA表达的增高倍数明显较青年小鼠低,同时老年小鼠p-ATM、p-Chk2和p53蛋白的表达水平较青年小鼠降低;而淫羊藿苷能够提高老年小鼠在电离辐射情况下ATM、Chk2、p53基因的mRNA表达水平,并且能够提高老年小鼠p-ATM、p-Chk2和p-p53蛋白表达水平。结论淫羊藿苷能够激活DNA损伤检验点ATM-Chk2-p53通路功能,这可能是淫羊藿苷延缓小鼠衰老的重要机制之一。 展开更多
关键词 衰老 淫羊藿苷 atm-chk2-p53通路
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DNA损伤检验点ATM-chk2通路影响衰老的作用机制分析
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作者 陈小敏 张素琴 《中国现代医生》 2013年第15期37-38,41,共3页
目的分析DNA损伤检验点ATM-chk2通路对影响衰老的作用机制。方法选择SD大鼠4个月龄、12个月龄、20个月龄和28个月龄各10只,分别取4个月龄、12个月龄、20个月龄和28个月龄大鼠的骨髓组织进行ATM-chk2通路的观察,并对结果进行分析。结果 ... 目的分析DNA损伤检验点ATM-chk2通路对影响衰老的作用机制。方法选择SD大鼠4个月龄、12个月龄、20个月龄和28个月龄各10只,分别取4个月龄、12个月龄、20个月龄和28个月龄大鼠的骨髓组织进行ATM-chk2通路的观察,并对结果进行分析。结果 4个月龄、12个月龄、20个月龄和28个月龄SD大鼠的ATM基因表达随着月龄增加,呈逐渐下降趋势,不同月龄大鼠间比较,差异具有显著性(P<0.05);ATM-chk2通路基因蛋白表达呈逐渐上升趋势,组间比较差异具有显著性(P<0.05)。结论 ATM基因表达及ATM-chk2通路基因蛋白表达水平和大鼠月龄直接相关,年龄越大ATM基因表达日渐降低,ATM-chk2通路基因蛋白表达呈逐渐上升趋势。 展开更多
关键词 DNA损伤检验点 ATM—chk2通路 衰老
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Validation of the “HY-2” altimeter wet tropospheric path delay correction based on radiosonde data 被引量:3
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作者 WANG Jin ZHANG Jie +1 位作者 FAN Chenqing WANG Jing 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第5期48-53,共6页
Wet tropospheric path delay (PD) is a highly variable term for the altimeter measurement of a sea surface height, caused by the refraction effect of atmospheric water vapor and cloud liquid water. In order to esti- ... Wet tropospheric path delay (PD) is a highly variable term for the altimeter measurement of a sea surface height, caused by the refraction effect of atmospheric water vapor and cloud liquid water. In order to esti- mate PD values, the "HY-2" system includes a calibration microwave radiometer (CMR) operating at 18.7, 23.8 and 37 GHz. The PD data of the CMR were compared and validated by coincident radiosonde profiles from ten globally distributed radiosonde stations during October 2011 to August 2012. The temporal interval was 1 h. In order to avoid land contamination, different spatial intervals between these two data sets were tested. The empirical fit function of PD uncertainty and spatial interval was found and extrapolated to the ideal situation that the data of CMR and radiosonde were totally coincident. The stability of the brightness temperature of the CMR and its impact on the PD correction was also studied. Consequently, the uncertainty of the PD algorithm of the CMR was estimated to be 2.1 cm. 展开更多
关键词 path delay "HY-2 satellite RADIOSONDE microwave radiometer brightness temperature
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Panax notoginseng saponins ameliorates experimental hepatic fibrosis and hepatic stellate cell proliferation by inhibiting the Jak2/Stat3 pathways 被引量:31
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作者 Jiang Hui Gao Jiarong +5 位作者 Wang Yongzhong Zhang Jiafu Han Yanquan Wei Liangbing Liu Xiaochuang Wu Jian 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2016年第2期217-224,共8页
OBJECTIVE: To investigate the inhibitory effect of Panax notoginseng saponins(PNS) on liver fibrosis and explore the underlying mechanisms.METHODS: Carbon tetrachloride(CCl4)-treated rats and hepatic stellate ce... OBJECTIVE: To investigate the inhibitory effect of Panax notoginseng saponins(PNS) on liver fibrosis and explore the underlying mechanisms.METHODS: Carbon tetrachloride(CCl4)-treated rats and hepatic stellate cells(HSCs) were used. The effect of PNS on CCl4-induced liver fibrosis was studied with histochemical and biochemical analysis.Transforming growth factor(TGF)-β1, α-smooth muscle actin(α-SMA), and collagen Ι m RNA expression were determined by reverse transcriptase-polymerase chain reaction(RT-PCR). Mean-while, the protein expression levels of α-SMA, collagen Ι, phosphorylation-Janus activated kinase signal transducer(p-Jak2) / Jak2, and phosphorylation-activator of transcription(p-Stat)3 / Stat3 were determined by immunohistochemistry and / or immunoblotting.RESULTS: PNS treatment significantly improved the liver function of rats as indicated by decreased serum enzymatic activities of alanine aminotransferase and aspartate aminotransferase. Histopathological results indicated that PNS alleviated liver damage and reduced the formation of fibrous septa. Moreover, PNS significantly decreased liver hydroxyproline and significantly attenuated expressions of collagen p-Stat3 / StatⅠ, α-SMA, TGF-β1, p-Jak2 / Jak2,and 3 in the rat liver fibrosis model and HSCs.CONCLUSION: PNS can relieve liver fibrosis by modulating Jak2/Stat3 signaling transduction pathway, which may be one of its mechanisms to suppress hepatic fibrosis. 展开更多
关键词 Sanchinoside Liver fibrosis Carbon tet rachloride Hepatic stellate cells Jak2/Stat3 path way
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An Optimal Feed Interpolator Based on G^2 Continuous Bézier Curves for High-Speed Machining of Linear Tool Path 被引量:7
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作者 Yongqiao Jin Sheng Zhao Yuhan Wang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第3期109-118,共10页
A numerical control (NC) tool path of digital CAD model is widely generated as a set of short line segments in machining. However, there are three shortcomings in the linear tool path, such as discontinuities of tange... A numerical control (NC) tool path of digital CAD model is widely generated as a set of short line segments in machining. However, there are three shortcomings in the linear tool path, such as discontinuities of tangency and curvature, huge number of line segments, and short lengths of line segments. These disadvantages hinder the development of high speed machining. To smooth the linear tool path and improve machining efficiency of short line segments, this paper presents an optimal feed interpolator based on G^2 continuous Bézier curves for the linear tool path. First, the areas suitable for fitting are screened out based on the geometric characteristics of continuous short segments (CSSs). CSSs in every area are compressed and fitted into a G^2 Continuous Bézier curve by using the least square method. Then a series of cubic Bézier curves are generated. However, the junction between adjacent Bézier curves is only G^0 continuous. By adjusting the control points and inserting Bézier transition curves between adjacent Bézier curves, the G^2 continuous tool path is constructed. The fitting error is estimated by the second-order Taylor formula. Without iteration, the fitting algorithm can be implemented in real-time environment. Second, the optimal feed interpolator considering the comprehensive constraints (such as the chord error constraint, the maximum normal acceleration, servo capacity of each axis, etc.) is proposed. Simulation and experiment are conducted. The results shows that the proposed method can generate smooth path, decrease the amount of segments and reduce machining time for machining of linear tool path. The proposed research provides an effective method for high-speed machining of complex 2-D/3-D profiles described by short line segments. 展开更多
关键词 G^2 CONTINUOUS path Least SQUARE method High-speed MACHINING CONTINUOUS short SEGMENTS Optimal FEED INTERPOLATOR Data compression
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2-G-Motzkin路上的计数问题
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作者 杨胜良 张愉媛 《兰州理工大学学报》 北大核心 2025年第3期150-155,共6页
引入2-G-Motzkin路的概念,利用符号化方法,拉格朗日反演公式和Riordan矩阵研究了2-G-Motzkin路上的一些计数问题,给出了相应的发生函数和计算公式.
关键词 2-G-Motzkin路 符号化方法 拉格朗日反演公式 Riordan矩阵 发生函数
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Influence of Solvent on Reaction Path to Synthesis of Methyl N-Phenyl Carbamate from Aniline, CO_2 and Methanol 被引量:3
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作者 安华良 张丽丽 +2 位作者 苑保国 赵新强 王延吉 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第5期607-610,共4页
Methyl N-phenyl carbamate(MPC), an important organic chemical, can be synthesized from aniline,CO2 and methanol. Catalyst Cu-Fe/ZrO2-SiO2 was first prepared and its catalytic performance for MPC synthesis was evaluate... Methyl N-phenyl carbamate(MPC), an important organic chemical, can be synthesized from aniline,CO2 and methanol. Catalyst Cu-Fe/ZrO2-SiO2 was first prepared and its catalytic performance for MPC synthesis was evaluated. Then the influence of solvent on the reaction path of MPC synthesis was investigated. It is found that the reaction intermediate is different with acetonitrile or methanol as a solvent. With acetonitrile as a solvent,the synthesis of MPC follows the reaction path with diphenyl urea as the intermediate, while with methanol as a solvent the reaction occurs via the reaction path with dimethyl carbonate as the intermediate. The catalytic mechanism of cooperative catalysis comprising metal sites, Lewis acid sites and Lewis base sites is proposed according to different reaction intermediates. 展开更多
关键词 reaction path methyl N-phenyl carbamate CO2 ANILINE METHANOL Cu-Fe/ZrO2-SiO2 catalyst
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An automated approach to calculating the maximum diameters of multiple cutters and their paths for sectional milling of centrifugal impellers on a 4_(1/2)-axis CNC machine 被引量:5
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作者 Baohai WU Zezhong C.CHEN +2 位作者 Ming LUO Dinghua ZHANG Feiyan HAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第4期1030-1039,共10页
Power generators and chemical engineering compressors include heavy and large centrifugal impellers. To produce these impellers in high-speed machining, a 4?-axis milling machine(or a 4-axis machine plus an indexing t... Power generators and chemical engineering compressors include heavy and large centrifugal impellers. To produce these impellers in high-speed machining, a 4?-axis milling machine(or a 4-axis machine plus an indexing table) is often used in the industry, which is more rigid than a5-axis milling machine. Since impeller blades are designed with complex B-spline surfaces and impeller channels spaces vary significantly, it is more efficient to use multiple cutters as large as possible to cut a channel in sections and a blade surface in patches, instead of only using a small cutter to machine a whole blade and a channel. Unfortunately, no approach has been established to automatically calculate the largest diameters of cutters and their paths, which include the indexing table angles. To address this problem, an automated and optimization approach is proposed. Based on the structure of a 4?-axis machine, a geometric model for a cutter gouging/interfering the impeller is formulated, and an optimization model of the cutter diameter in terms of the indexing table angle is established at a cutter contact(CC) point on a blade surface. Then, the diameters of the tools,their orientations, and the indexing table angles are optimized, and each tool's paths are generated for machining its corresponding impeller section. As a test, an impeller is efficiently machined with these tools section by section; thus, this approach is valid. It can be directly used in the industry to improve efficiency of machining centrifugal impellers. 展开更多
关键词 Automated path generation 4_(1/2)-Axis CNC machining Centrifugal impeller machining Cutter diameter optimization Sectional machining
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基于PLCγ/PKC/Ca^(2+)信号通路探讨防风水提物对小鼠过敏性鼻炎的影响
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作者 陈思思 丁泽杰 陈艳春 《浙江中医杂志》 2025年第6期471-475,共5页
目的:研究防风水提物对小鼠过敏性鼻炎的治疗作用。方法:将36只雌性Balb/c小鼠随机分为对照组、模型组、低、中、高(防风水提物4、8、16mg/kg)剂量组和阳性药组(地塞米松5mg/kg),每组6只。末次干预后,记录打喷嚏、挠鼻次数。通过苏木素... 目的:研究防风水提物对小鼠过敏性鼻炎的治疗作用。方法:将36只雌性Balb/c小鼠随机分为对照组、模型组、低、中、高(防风水提物4、8、16mg/kg)剂量组和阳性药组(地塞米松5mg/kg),每组6只。末次干预后,记录打喷嚏、挠鼻次数。通过苏木素-伊红染色和甲苯胺蓝染色观察鼻腔组织病理变化;酶联免疫吸附试验检测血清中白三烯C4、组胺、白介素4(IL-4)及免疫球蛋白的水平。Western blot法检测鼻腔组织PLCγ、PKC蛋白的表达水平。用不同剂量防风水提物和阳性药处理RBL-2H3细胞,检测β-己糖胺酶释放率和细胞中Ca^(2+)荧光强度的变化。结果:防风水提物能减少小鼠打喷嚏、挠鼻的次数(P<0.05或0.01),减少肥大细胞数量(P<0.01),降低白三烯C4、组胺、IL-4及免疫球蛋白水平,抑制PLCγ、PKC的表达(P<0.05或0.01);使β-己糖胺酶的释放率和Ca^(2+)浓度下降(P<0.05或0.01)。结论:防风水提物可能通过抑制PLCγ/PKC/Ca^(2+)信号通路改善小鼠的过敏性鼻炎。 展开更多
关键词 防风水提物 过敏性鼻炎 肥大细胞 脱颗粒 PLCγ/PKC/Ca^(2+)信号通路 小鼠
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Preliminary research on the transmission path of nssSO_4^(2-) and NO_3^- in Antarctic ice sheet 被引量:1
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作者 张明军 李忠勤 +4 位作者 秦大河 效存德 杨惠安 康建成 李军 《Chinese Journal of Polar Science》 2001年第1期48-52,共5页
The main sources of nssSO 2- 4 and NO - 3 were summarized in this paper. By analyzing the spatial distribution features of major ions in Antarctic ice sheet and studying on the different time of the same volca... The main sources of nssSO 2- 4 and NO - 3 were summarized in this paper. By analyzing the spatial distribution features of major ions in Antarctic ice sheet and studying on the different time of the same volcanic event recorded by different ice cores from different regions in Antarctica, this paper intends to study the transmission path of nssSO 2- 4 and NO - 3. Results show that nssSO 2- 4 and NO - 3 are transmitted to the ice sheet through long distance and high altitude. The procedure of the transmission is that nssSO 2- 4 and NO - 3 are transmitted to the level between the top of troposphere and the bottom of stratosphere, then subsided to the ice sheet surface and spread to other regions. 展开更多
关键词 Antarctic ice sheet nssSO 2- 4 NO - 3 transmission path.
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Quantum Path Selection and Isolated-Attosecond-Pulse Generation of H2+ with an Intense Laser Pulse and a Static Field 被引量:1
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作者 苗向阳 刘莎莎 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第1期42-46,共5页
We theoretically investigate the high-order-harmonic generation from the H2^+ molecular ion exposed to the combi- nation of an intense trapezoidal laser and a static field. The results show that the harmonic spectrum... We theoretically investigate the high-order-harmonic generation from the H2^+ molecular ion exposed to the combi- nation of an intense trapezoidal laser and a static field. The results show that the harmonic spectrum is obviously extended and the short quantum path is selected to contribute to the spectrum, because the corresponding long path is seriously suppressed. Then the combined Coulomb and laser field potentials and the time-dependent electron wave packet distributions are applied to illustrate the physical mechanism of high-order harmonic gen- eration. Finally, by adjusting the intensity of the static field and superposing a properly selected range of the HHG spectrum, a 90-as isolated attosecond pulse is straightforwardly obtained. 展开更多
关键词 Quantum path Selection and Isolated-Attosecond-Pulse Generation of H2 with an Intense Laser Pulse and a Static Field
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长期施用有机肥和化肥对黑土N_(2)O排放的影响 被引量:2
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作者 王昊 胡荣桂 +4 位作者 林杉 高洪军 徐明岗 张文菊 邬磊 《环境科学》 北大核心 2025年第4期2621-2628,共8页
东北黑土区作为我国重要的粮食生产基地,近年来面临着土壤退化、肥力下降和粮食减产等诸多问题.优化施肥管理是维持或提升土壤肥力的一种重要措施,但不合理的肥料施用会促使养分损失和N_(2)O等温室气体排放,导致土壤退化和环境污染.为... 东北黑土区作为我国重要的粮食生产基地,近年来面临着土壤退化、肥力下降和粮食减产等诸多问题.优化施肥管理是维持或提升土壤肥力的一种重要措施,但不合理的肥料施用会促使养分损失和N_(2)O等温室气体排放,导致土壤退化和环境污染.为探明黑土N_(2)O排放对长期施用有机肥和化肥的响应及关键控制因素,采集吉林公主岭黑土长期定位试验(32 a)的施用有机肥主处理(M_(0),不施有机肥;M_(1),低量有机肥;M_(2),高量有机肥)和施用化肥副处理(CK,不施肥;N,化学氮肥;NPK,化学氮磷钾肥)共计9个处理(即每个施用有机肥水平下包含3个化肥施用水平)的表层土壤样品(0~20 cm),进行室内恒温恒湿培养(65%田间持水量25℃下培养21 d),并测定N_(2)O排放通量和土壤物理化学生物学性质.研究结果表明,长期施用有机肥和化肥显著增加了黑土N_(2)O排放.与M_(0)CK处理[(0.25±0.01)mg·kg^(−1),以N计,下同]相比,单施有机肥处理N_(2)O累计排放量显著提高了361%~456%[M_(1)CK和M_(2)CK处理分别为(1.17±0.02)mg·kg^(−1)和(1.41±0.02)mg·kg^(−1)],且N_(2)O排放随着有机肥施用量增加显著增强.与M_(0)CK处理相比,单施化肥处理N_(2)O累计排放量显著提高了96%~236%[M_(0)N和M_(0)NPK处理分别为(0.49±0.01)mg·kg^(−1)和(0.84±0.03)mg·kg^(−1)],且平衡施用化肥处理N_(2)O排放提升幅度明显高于单施氮肥处理.在M_(1)和M_(2)条件下,化肥施用对N_(2)O排放的影响程度减弱,说明有机肥施用缓解了化肥对N_(2)O排放的影响.单施有机肥显著提高了土壤及团聚体有机碳(SOC)和总氮(TN)、土壤微生物量碳氮含量,有机肥配施进一步提高土壤及团聚体SOC和TN含量.Pearson相关及路径分析结果表明,N_(2)O排放与土壤碳氮组分及微生物量碳氮含量显著正相关,长期施用有机肥和化肥主要通过影响土壤碳氮组分,改变微生物量和底物有效性调控N_(2)O排放.综上所述,施用有机肥通过增加土壤可利用碳氮库以及微生物生物量碳氮显著促进了N_(2)O排放.有机肥施用缓解了化肥对N_(2)O排放的促进作用,在施用化肥时应适量配施有机肥,以平衡肥力提升与氮素损失及温室气体排放的综合效应. 展开更多
关键词 长期施肥 碳氮组分 N_(2)O 土壤团聚体 偏最小二乘法路径分析模型(PLS-PM)
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Tracy-Widom distribution, Airy2 process and its sample path properties
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作者 SU Zhong-gen LEI Yu-huan SHEN Tian 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2021年第1期128-158,共31页
Tracy-Widom distribution was rst discovered in the study of largest eigenvalues of high dimensional Gaussian unitary ensembles(GUE),and since then it has appeared in a number of apparently distinct research elds.It is... Tracy-Widom distribution was rst discovered in the study of largest eigenvalues of high dimensional Gaussian unitary ensembles(GUE),and since then it has appeared in a number of apparently distinct research elds.It is believed that Tracy-Widom distribution have a universal feature like classic normal distribution.Airy2 process is de ned through nite dimensional distributions with Tracy-Widom distribution as its marginal distributions.In this introductory survey,we will briey review some basic notions,intuitive background and fundamental properties concerning Tracy-Widom distribution and Airy2 process.For sake of reading,the paper starts with some simple and well-known facts about normal distributions,Gaussian processes and their sample path properties. 展开更多
关键词 Airy2 process Dyson Brownian motion Tracy-Widom distribution sample path property.
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New paths and research directions in CO_(2) conversion by electro-, photoand plasma catalysis
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作者 Claudio Ampelli Maria L.Carreon Yuefeng Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第12期300-301,共2页
CO_(2) conversion into value-added products by electro-, photoand plasma catalysis under mild operating conditions(ambient temperature and pressure) is an emerging area to achieve carbon circularity by producing chemi... CO_(2) conversion into value-added products by electro-, photoand plasma catalysis under mild operating conditions(ambient temperature and pressure) is an emerging area to achieve carbon circularity by producing chemicals and fuels using directly renewable energy. Among all CO_(2) conversion approaches, the electrocatalytic reduction of CO_(2) is the most mature technology, capable of achieving high productivity(i.e. high current densities) at large scale, especially for producing carbon monoxide(CO), but with many examples showing selectivity to C_(2) carbon products. 展开更多
关键词 New paths and research directions in CO_(2)conversion by electro photoand plasma catalysis
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Total flavonoids of Scutellaria barbata improving podocyte injury induced by high glucose through Smad4/PKM2/HIF‑1α pathway
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作者 YAN Dong GU Chang‑rui ZHANG Xiang 《Journal of Hainan Medical University》 2023年第2期22-28,共7页
Objective: To observe the effect of total flavonoids of Scutellaria barbata (TF‑SB) on the injury of high glucose induced podocytes (MPC‑5) and the influence of Smad4/PKM2/HIF‑1α pathway. Methods: Firstly, CCK8 was u... Objective: To observe the effect of total flavonoids of Scutellaria barbata (TF‑SB) on the injury of high glucose induced podocytes (MPC‑5) and the influence of Smad4/PKM2/HIF‑1α pathway. Methods: Firstly, CCK8 was used to analyze the safety and efficacy concentration of TF‑SB on MPC‑5 cells. Then, MPC‑5 was then divided into the control group, model group and TF‑SB group. In addition to the control group, model group and TF‑SB group were induced by high glucose to establish MPC‑5 cell injury model. The effects of TF‑SB on ATP, apoptosis and ROS levels of MPC‑5 cells were detected respectively. The contents of IL‑1β, TNF‑α, and MCP‑1 were determined by ELISA, the expression abundance of glycolytic genes (GLU1, PFK1 and HK1) were detected by RT‑PCR. Western blot method was used to detect the expression level of related proteins in Smad4/PKM2/HIF‑1α pathway. Results: Compared with the blank group, ATP content, GLU1, PKF1 and HK1 expression abundance of MPC‑5 cells in the model group decreased significantly, apoptosis, ROS level and IL‑1 β、 TNF‑ α And MCP‑1 significantly increased (P<0.01);Compared with model group, ATP content, GLU1, PKF1 and HK1 expression abundance, apoptosis, ROS level and IL‑1β in TF‑SB group were significantly increased , TNF‑ α The contents of MCP‑1 and MCP‑1 decreased significantly (P<0.01). In addition, compared with the blank group, the model group Smad4 and HIF‑1 α The protein expression and PKM2 expression in nucleus were significantly increased, while PKM2 expression in cytoplasm was significantly decreased (P<0.01);Compared with model group, TF‑SB group Smad4, HIF‑1 α The expression of PKM2 in the nucleus and expression of PKM2 were significantly decreased, while the expression of PKM2 in the cytoplasm was significantly increased (P<0.01). Conclusion: TF‑SB promotes the mitochondrial activity of MPC‑5 cells to induce glycolysis, and then inhibits the secretion of inflammation, which may play a role in treating diabetes nephropathy by inhibiting Smad4/PKM2/HIF‑1α signaling pathway. 展开更多
关键词 TF‑SB Diabetes nephropathy PODOCYTES Smad4/PKM2/HIF‑1αsignal path
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Hamiltonian, Path Integral and BRST Formulations of the Restricted Gauge Theory of <i>QCD<sub>2</sub></i>
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作者 Usha Kulshreshtha Daya Shankar Kulshreshtha James P. Vary 《Journal of Modern Physics》 2018年第14期2355-2369,共15页
We study the Hamiltonian, path integral and Becchi-Rouet-Stora and Tyutin (BRST) formulations of the restricted gauge theory of QCD2 à la Cho et al. under appropriate gauge-fixing conditions.
关键词 HAMILTONIAN QUANTIZATION path Integral QUANTIZATION BRST QUANTIZATION Quantum CHROMODYNAMICS QCD2 Field Theories in Lower Dimensions Gauge-Invariant Theories Gauge-Fixing
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基于K-means与2-Opt改进的贪心路径优化算法研究 被引量:1
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作者 黄启华 冯子俊 +1 位作者 杜玉晓 王烁哲 《自动化与信息工程》 2025年第2期9-17,共9页
针对当前衣物裁剪路径优化算法无法同时满足高精度和低时间消耗的问题,提出基于K-means与2-Opt改进的贪心路径优化算法。首先,利用K-means聚类算法进行大规模旅行商问题的局部分组;然后,采用2-Opt改进的贪心算法优化路径;最后,通过最近... 针对当前衣物裁剪路径优化算法无法同时满足高精度和低时间消耗的问题,提出基于K-means与2-Opt改进的贪心路径优化算法。首先,利用K-means聚类算法进行大规模旅行商问题的局部分组;然后,采用2-Opt改进的贪心算法优化路径;最后,通过最近邻连接方法对子问题的解进行类间连接。实验结果验证了该算法具有较好的路径和效率优化能力。 展开更多
关键词 衣物裁剪路径优化 K-MEANS聚类算法 2-Opt算法 贪心算法
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基于多波段LED长光程DOAS技术的合肥郊区HONO和NO_(2)观测研究
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作者 高齐 邢成志 +2 位作者 林华 麻万超 刘文清 《大气与环境光学学报》 2025年第6期713-725,共13页
利用基于多波段LED耦合光源搭建的长光程差分光学吸收光谱(LP-DOAS)系统,在2022年3―5月对合肥郊区春季NO_(2)和HONO的质量浓度进行了高时间分辨率连续监测。研究发现NO_(2)的月均质量浓度表现为3月(19.00μg/m^(3))> 4月(16.03μg/m... 利用基于多波段LED耦合光源搭建的长光程差分光学吸收光谱(LP-DOAS)系统,在2022年3―5月对合肥郊区春季NO_(2)和HONO的质量浓度进行了高时间分辨率连续监测。研究发现NO_(2)的月均质量浓度表现为3月(19.00μg/m^(3))> 4月(16.03μg/m^(3))> 5月(14.66μg/m^(3));HONO的月均质量浓度表现为5月(1.42μg/m^(3))> 4月(1.31μg/m^(3))> 3月(1.25μg/m^(3)),同时多波段LED LP-DOAS监测的NO_(2)质量浓度与国控站点监测的NO_(2)质量浓度相关系数R达0.895。鉴于NO_(2)主要来自交通排放,其最低质量浓度出现在14:00;白天HONO的高质量浓度出现在08:00、12:00―13:00和16:00―18:00,分别对应NO_(2)的3个较高质量浓度时段,表明NO_(2)在湿表面的非均相反应可能是HONO的重要来源。此外,研究还发现NO_(2)和HONO在周末11:00―15:00期间的质量浓度高于其在工作日相应时段的质量浓度。进一步分析表明,PM_(2.5)和大气相对湿度会影响NO_(2)非均相反应生成HONO的速率;观测期间PM_(2.5)质量浓度和大气相对湿度越大,则NO_(2)和HONO的拟合斜率越大,表明HONO的生成速率越大。 展开更多
关键词 多波段LED 长光程差分吸收光谱 NO_(2) HONO 非均相反应
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