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氮肥减量与追施方式对小麦产量和氮肥利用效率及麦田N_(2)O排放的影响
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作者 石吕 石晓旭 +11 位作者 韩笑 单海勇 刘旭杰 张晋 严旖旎 李赢 刘海翠 魏亚凤 杨美英 薛亚光 刘建 张祖建 《作物学报》 北大核心 2026年第1期202-220,共19页
为探究稻茬小麦深施肥“一基一追”机艺融合技术的增产增效减排机制,2021—2024年在长江下游南通稻茬麦区开展大田试验。试验采用缓释掺混肥料(SRF,N∶P_(2)O_(5)∶K_(2)O=26∶12∶12)和普通尿素(U,46%N),结合自主研发的2BFGK-12(6)260... 为探究稻茬小麦深施肥“一基一追”机艺融合技术的增产增效减排机制,2021—2024年在长江下游南通稻茬麦区开展大田试验。试验采用缓释掺混肥料(SRF,N∶P_(2)O_(5)∶K_(2)O=26∶12∶12)和普通尿素(U,46%N),结合自主研发的2BFGK-12(6)260全秸秆茬地洁区旋耕智能施肥播种机和3ZF-4(200)中耕追肥机,设置7种施肥模式(30 cm+15 cm宽窄行种植):以尿素4次分施(N 240 kg hm^(-2),基肥∶分蘖肥∶拔节肥∶孕穗肥=5∶1∶2∶2,窄行基施,追肥全田撒施)为对照(CK);减氮15%(N 204 kg hm^(-2))条件下设置6种处理:M_(1)(100%SRF窄行基施);M_(2)(60%SRF窄行基施+40%U拔节期窄行撒施);M_(3)(60%SRF窄行基施+40%U返青期宽行条施);M_(4)(60%SRF窄行基施+40%SRF返青期窄行撒施);M_(5)(60%SRF窄行基施+40%SRF返青期宽行条施);M_(4+5)(60%SRF窄行基施+20%SRF返青期宽行条施+20%SRF返青期窄行撒施)。研究比较不同施肥模式对小麦产量效益、根系形态生理、氮素利用效率及N_(2)O排放的影响。结果表明,与CK相比,M_(2)~M_(5)处理提高了小麦产量(4.0%~19.0%)和经济效益(13.7%~35.7%),其中M_(4)和M_(5)处理表现最优,分别增产14.1%和19.0%,经济效益提升34.5%和35.7%。这些处理明显改善了根系特性(根干重密度增加9.7%~111.8%,根系活力和氧化力分别提高6.8%~52.0%和4.2%~44.2%),降低N_(2)O累积排放量22.6%~34.5%,提高0~20 cm土层硝态氮含量11.2%~40.0%。在氮素利用方面,M_(2)~M_(5)处理均提高了籽粒氮素积累量、花后氮素积累量及其对籽粒氮素的贡献率,氮肥利用效率指标(包括偏生产力、农学效率和表观利用率)分别显著提升了22.4%~40.0%、29.7%~74.3%和9.41~18.77个百分点。值得注意的是,M_(4)和M_(5)处理表现出最优的综合效益:N_(2)O累积排放量降幅最大(分别达27.0%和34.5%),氮肥表观利用率2季均维持在43.0%以上(均值分别为43.5%和46.8%),同时在生育后期保持较高的根系活性和耕层无机氮含量。相比之下,M_(1)处理虽然实现了最大的N_(2)O减排效果(降幅35.9%),但导致减产10.4%和经济效益下降10.8%,且氮肥利用效率呈现不稳定的年际变化特征。而优化处理M_(4+5)进一步改善了根系形态生理特性,并提高氮肥表观利用率和籽粒氮素积累量。综上,减氮15%条件下(N 204 kg hm^(-2)),缓混肥2次施用处理(M_(4)和M_(5))能实现产量、经济效益、氮肥利用效率和N_(2)O减排的协同提高,并以追肥深施处理(M_(5))效应更强。本研究为稻茬小麦缓释肥减氮优化高效应用提供重要理论依据。 展开更多
关键词 条带耕作 氮肥减量 追肥方式 产量 氮肥利用 N_(2)o排放
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Steel's CO_2 balance—a contribution to climate protection
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作者 Gerhard ENDEMANN 《Baosteel Technical Research》 CAS 2010年第S1期130-,共1页
Steel making is energy and material intensive.That is why steel is always demonized and confronted with incriminations and requirements for reduction of its environmental impact.Those pure demands-like for emission tr... Steel making is energy and material intensive.That is why steel is always demonized and confronted with incriminations and requirements for reduction of its environmental impact.Those pure demands-like for emission trading are short-sighted as they do not base on an integrated approach.Instead they merely consider CO_2 emissions during the production process.A forward-looking,global climate and environmental policy needs a sustainable life cycle approach.Therefore it must for example also take into account the contribution of steel towards cutting emissions in its application-in the energy.automotive and household sectors.Steel will play a key role in climate protection. One-third of the remaining CO_2 reduction target planned in Germany by 2020 can only be achieved with the help of innovative steel products and their applications.This is the conclusion of an independent study by The Boston Consulting Group(BCG) on behalf of Steel Institute VDEh,and German Steel Federation.The study compares CO_2 savings from important innovative steel applications(such as more efficient power stations,wind turbines,or lighter vehicles) with CO_2 emissions caused by steel production. By adopting this comprehensive perspective,the study for the first time provides a CO_2 balance for the material steel by comparing the CO_2 reductions made possible through innovative steel applications with the CO_2 emissions resulting from steel production.The balance was calculated on the basis of eight selected innovative steel applications in Germany for the period 2007 to 2020,whereby the CO_2 emissions caused by steel production were considered throughout the entire life cycle of the particular steel use.For the selected examples,the use of innovative steels resulted in a total savings potential of 74 Mt of CO_2 in 2020.The calculations are based on conservative assumptions;for example without counting of potentials by exported steel or by comparison with competitive materials. The production of steel in Germany,including the extraction of raw materials,transports and further processing, causes annual emissions of approx.67 Mt CO_2 This can be more than compensated by the above mentioned CO_2 savings.The balance is even more positive if one only considers the emissions of about 12 Mt/a CO_2 caused by the selected eight steel applications.Innovative steel use thus saves six times as much CO_2 as is generated by its production. Steel is part of the story and helps to achieve CO_2 reduction targets.On this basis the steel industry should start up with a new global approach to be accepted as a CO_2 killer,too,instead of being the devil.This needs a political discussion on an integrated approach taking into account the whole life cycle,which finally can lead away from stringent emission caps or incompatible emissions trading systems for the different regions. 展开更多
关键词 STEEL life cycle product Co_2 balance emission cutting climate protection
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新型倒置A^(2)/O耦联MBR组合工艺处理农村低C/N废水的研究 被引量:1
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作者 韩卫萍 盖磊 《水处理技术》 CAS 北大核心 2025年第1期114-119,共6页
针对农村低C/N污水污染物和营养盐去除率差的问题,以倒置A^(2)/O耦联膜生物反应器(MBR)组合工艺为探究对象,通过控制进水污染物浓度,在中温条件下考察了有机负荷(OLR)对倒置A^(2)/O耦联MBR组合工艺处理农村低C/N污水的影响。结果表明,OL... 针对农村低C/N污水污染物和营养盐去除率差的问题,以倒置A^(2)/O耦联膜生物反应器(MBR)组合工艺为探究对象,通过控制进水污染物浓度,在中温条件下考察了有机负荷(OLR)对倒置A^(2)/O耦联MBR组合工艺处理农村低C/N污水的影响。结果表明,OLR由150 mg/L提高至450 mg/L时,总氮(TN)和溶解性磷酸盐(SOP)去除率分别由67.6%和86.6%提高至72.4%和94.3%,进一步提高OLR降低了组合工艺对污染物和营养盐的去除。此外,OLR能影响新工艺内污泥特征,提高OLR促进了胞外聚合物(EPS)分泌,尤其在OLR为600 mg/L组别内,EPS含量提高至139.6 mg/g。进水OLR对缺氧池内EPS的影响要大于其对厌氧池内EPS的影响。OLR能影响新工艺内污染物和营养盐去除相关关键酶的活性,当OLR为450 mg/L时,污染物和营养盐去除相关关键活性酶最强。研究结果为农村低C/N污水的高效处理提供了理论依据和数据支撑。 展开更多
关键词 农村低C/N污水 倒置A^(2)/o MBR 胞外聚合物 关键酶
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膜曝气生物膜反应器污水处理过程N_(2)O排放特性及减排策略 被引量:2
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作者 王亚宜 贺泰来 +3 位作者 李佳 吴巧玉 汪涵 赵立功 《北京工业大学学报》 北大核心 2025年第3期350-358,共9页
膜曝气生物膜反应器(membrane aerated biofilm reactor,MABR)作为一种新型的污水处理技术,因其高效的氮去除能力和较低的N_(2)O排放水平而受到广泛关注。传统污水处理脱氮过程中,硝化反硝化阶段主要通过羟胺氧化、AOB反硝化、异养反硝... 膜曝气生物膜反应器(membrane aerated biofilm reactor,MABR)作为一种新型的污水处理技术,因其高效的氮去除能力和较低的N_(2)O排放水平而受到广泛关注。传统污水处理脱氮过程中,硝化反硝化阶段主要通过羟胺氧化、AOB反硝化、异养反硝化以及化学变化途径产生N_(2)O。MABR处理市政污水较传统曝气方式具有更低的N_(2)O排放潜力,主要得益于MABR特殊的底物异向扩散模式和无泡曝气方式,这会减少N_(2)O产生潜力及排放水平。该文总结了MABR在运行过程中N_(2)O产生与降低途径,讨论了N_(2)O产生和排放的影响因素及控制策略,并对今后研究MABR体系中N_(2)O排放进行了展望,以期说明MABR进一步工程应用在碳减排方面的优势。 展开更多
关键词 膜曝气生物膜反应器(membrane aerated biofilm reactor MABR) N_(2)o 污水处理 温室气体 碳减排 生物脱氮
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SH2B1 regulation of energy balance, body weight, and glucose metabolism 被引量:5
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作者 Liangyou Rui 《World Journal of Diabetes》 SCIE CAS 2014年第4期511-526,共16页
The Src homology 2B(SH2B)family members(SH2B1,SH2B2 and SH2B3)are adaptor signaling proteins containing characteristic SH2 and PH domains.SH2B1(also called SH2-B and PSM)and SH2B2(also called APS)are able to form homo... The Src homology 2B(SH2B)family members(SH2B1,SH2B2 and SH2B3)are adaptor signaling proteins containing characteristic SH2 and PH domains.SH2B1(also called SH2-B and PSM)and SH2B2(also called APS)are able to form homo-or hetero-dimers via their N-terminal dimerization domains.Their C-terminal SH2 domains bind to tyrosyl phosphorylated proteins,including Janus kinase 2(JAK2),TrkA,insulin receptors,insulin-like growth factor-1 receptors,insulin receptor substrate-1(IRS1),and IRS2.SH2B1 enhances leptin signaling by both stimulating JAK2 activity and assembling a JAK2/IRS1/2 signaling complex.SH2B1 promotes insulin signaling by both enhancing insulin receptor catalytic activity and protecting against dephosphorylation of IRS proteins.Accordingly,genetic deletion of SH2B1 results in severe leptin resistance,insulin resistance,hyperphagia,obesity,and type 2 diabetes in mice.Neuronspecific overexpression of SH2B1βtransgenes protects against diet-induced obesity and insulin resistance.SH2B1 in pancreaticβcells promotesβcell expansion and insulin secretion to counteract insulin resistance in obesity.Moreover,numerous SH2B1 mutations are genetically linked to leptin resistance,insulin resistance,obesity,and type 2 diabetes in humans.Unlike SH2B1,SH2B2 and SH2B3 are not required for the maintenance of normal energy and glucose homeostasis.The metabolic function of the SH2B family is conserved from insects to humans. 展开更多
关键词 obesity Type 2 diabetes Leptin RESISTANCE Insulin RESISTANCE Glucose INToLERANCE HYPoTHALAMUS Energy balance Food intake HYPERPHAGIA NoNALCoHoLIC FATTY liver disease
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Ribavirin contributes to eradicate hepatitis C virus through polarization of T helper 1/2 cell balance into T helper 1 dominance 被引量:6
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作者 Katsuhisa Nakatsuka Masanori Atsukawa +2 位作者 Masumi Shimizu Hidemi Takahashi Chiaki Kawamoto 《World Journal of Hepatology》 CAS 2015年第25期2590-2596,共7页
The mechanism of action of ribavirin(RBV) as an immunomodulatory and antiviral agent and its clinical significance in the future treatment of patients with hepatitis C virus(HCV) infection are reviewed.RBV up-regulate... The mechanism of action of ribavirin(RBV) as an immunomodulatory and antiviral agent and its clinical significance in the future treatment of patients with hepatitis C virus(HCV) infection are reviewed.RBV up-regulates type 1 and/or 2 cytokines to modulate the T helper(Th) 1/2 cell balance to Th1 dominance.Examination of co-stimulatory signaling indicated that RBV down-modulates inducible co-stimulator on Th cells,which contributes to differentiating na?ve Th cells into Th2 cells while reducing their interleukin-10 production.The effects on T-regulatory(Treg) cells were also investigated,and RBV inhibited the differentiation of na?ve Th cells into adaptive Treg cells by downmodulating forkhead box-P3.These findings indicate that RBV mainly down-regulates the activity of Th2 cells,resulting in the maintenance of Th1 activity that contributes to abrogating HCV-infected hepatocytes.Although an interferon-free treatment regimen exhibits almost the same efficacy without serious complications,regimens with RBV will be still be used because of their ability to facilitate the cellular immune response,which may contribute to reducing the development of hepatocellular carcinogenesis in patients infected with HCV. 展开更多
关键词 RIBAVIRIN FoRKHEAD box-P3 T HELPER 1/2cell balance T-regulatory lymphocytes INDUCIBLE costimulator INTERLEUKIN-10 Hepatitis C virus infection
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Wang-Bi tablet, a patented Chinese medicine, maintains the balance of Th1/Th2 in mice with collagen-induced arthritis 被引量:6
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作者 Wang Jianming Luo Jing +4 位作者 Xu Yuan Yan Zeran Qu Xiangke Chen Mengxue Tao Qingwen 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2020年第3期401-406,共6页
OBJECTIVE: To investigate the pharmacological mechanism of Wang-Bi tablets(WBTs), a Chinese patented medicine, in rheumatoid arthritis(RA) using mice with collagen-induced arthritis(CIA).METHODS: A mouse model of CIA ... OBJECTIVE: To investigate the pharmacological mechanism of Wang-Bi tablets(WBTs), a Chinese patented medicine, in rheumatoid arthritis(RA) using mice with collagen-induced arthritis(CIA).METHODS: A mouse model of CIA was induced using bovine type Ⅱ collagen. WBT treatment was administered and efficacy was evaluated. The levels of interferon-γ(IFN-γ), interleukin-2(IL-2), and interleukin-4(IL-4) were examined using an enzyme-linked immunosorbent assay, and the proportions of Th1 and Th2 were detected using flow cytometry. T-bet and GATA-binding protein 3(GATA3)expression were demonstrated using Western blot analysis.RESULTS: Paw swelling and the arthritis index decreased significantly following WBT treatment. Histopathological analysis revealed markedly alleviated damage to synovium tissue in the WBT and methotrexate treatment groups. WBT regulated the production of IFN-γ, IL-2, and IL-4 and modulated Th1 and Th2 cell populations, which might have been induced by the attenuation of Th1 and Th2 cell differentiation through a decrease in the expression of T-bet and an increase in the expression of GATA3 in the synovial tissue in CIA mice.CONCLUSION: These results indicate that WBT may produce a therapeutic effect on CIA through maintaining the balance of Th1/Th2 cells, which could result in a decrease in the autoinflammatory disorder observed in RA. 展开更多
关键词 ARTHRITIS RHEUMAToID Collagen Th1-Th2 balance Wang-Bi tablet
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Hydrolyzed seawater pearl tablet modulates the immunity via attenuating Th1/Th2 imbalance in an immunosuppressed mouse model 被引量:12
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作者 LAN Taijin LUO Xuefei +10 位作者 MO Mingyue CHEN Zhenxing LUO Fei HAN Siyin LIU Peng LIANG Zhongxiu ZHANG Ting LI Tianyi YAN Qiangqiang LIN Yong LIN Jiang 《Journal of Traditional Chinese Medicine》 SCIE CSCD 2021年第3期397-405,共9页
OBJECTIVE: To investigate whether Hydrolyzed Seawater Pearl tablet(HSPT) could modulate the Th1/Th2 imbalance in an immunosuppressed mouse model with Th1 to Th2 shift induced by Cyclosporine A(Cs A) which can be used ... OBJECTIVE: To investigate whether Hydrolyzed Seawater Pearl tablet(HSPT) could modulate the Th1/Th2 imbalance in an immunosuppressed mouse model with Th1 to Th2 shift induced by Cyclosporine A(Cs A) which can be used in the clinical treatment of Th2 to Th1 shift diseases, and explore the possible mechanism for the adjuvant therapeutic efficacy of HSPT on recurrent respiratory infections(RRI) and acquired immune deficiency syndrome(AIDS).METHODS: The mice were randomly divided into six groups of five animals each, namely normal group, model group, lentinan polysaccharide tablet(LPT) group and three HPST treated groups. HPST treated groups were administered with HPST(0.51,1.02, 2.04 g/kg) via intragastric gavage(i.g) for 30 consecutive days. LPT used as reference drug for positive control, LPT group was administered with LPT(8.2 mg/kg) for 30 consecutive days. Normal group and model group were received distilled water. The animals in model group, LPT group and HPST treated groups were injected intraperitoneally with Cs A(50 mg/kg) to establish the immunosuppressed mice model with Th1 to Th2 shift on the20 th, 22 nd and 24 th day, one hour after the administration of the respective treatment. Animals were sacrificed one hour after the last administration to collect blood and splenic tissue. The proportion of T cells including CD8+ and CD4+ T cells, Th1 and Th2 in peripheral blood of experimental mice were measured by flow cytometric. The protein level in serum and m RNA level in splenic tissue of experimental mice for interleukin(IL)-2, IL-12, interferon-γ(IFN-γ), IL-4, IL-6, IL-10 and IL-13 were measured by enzyme linked immunosorbent assay and fluorescence quantitative polymerase chain reaction respectively.RESULTS: HSPT elevated the proportion of T cells including both CD8+ and CD4+ T cells, in which the proportion of Th1 and Th2 cells increased, while the ratio of Th1/Th2 cells decreased in peripheral blood of the immunosuppressed mouse model with Th1 to Th2 shift induced by Cs A. Furthermore,HSPT elevated both protein and m RNA level of Th1-type cytokines IL-2 and IFN-γ, while had no significant effect on protein and m RNA level of Th1-type cytokine IL-12 and Th2-type cytokines IL-4, IL-6, IL-10, IL-13 in mouse model.CONCLUSION: Our findings suggest that HSPT can increase proportion of T cells including both CD8+and CD4+T cells and induce Th2 to Th1 shift in both cells and cytokines, which probably was the mechanism to account for the adjuvant therapeutic efficacy of HSPT on RRI and AIDS. 展开更多
关键词 respiratory tract infections acquired immunodeficiency syndrome Th1-Th2 balance INTERLEUKINS INTERFERoN-GAMMA Hydrolyzed Seawater Pearl tablet
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倒置A^(2)/O+A生化法+膜法+磁混凝法污水处理工程实例
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作者 计建洪 耿学坚 +2 位作者 王丽聪 杭彩云 庄惠生 《印染》 北大核心 2025年第1期64-67,共4页
采用“倒置A^(2)/O+A生化法+膜法+磁混凝物化法”组合工艺处理污水,分析了工艺特点,并详述了主要构筑物及设备参数。该组合工艺处理效果优良,除磷脱氮效果好,出水COD、TP、NH_(3)-N、TN月均值分别为28、0.2、0.3、6.06mg/L,达到了DB32/1... 采用“倒置A^(2)/O+A生化法+膜法+磁混凝物化法”组合工艺处理污水,分析了工艺特点,并详述了主要构筑物及设备参数。该组合工艺处理效果优良,除磷脱氮效果好,出水COD、TP、NH_(3)-N、TN月均值分别为28、0.2、0.3、6.06mg/L,达到了DB32/1072—2018《太湖地区城镇污水处理厂及重点工业行业主要水污染物排放限值》其他区域污染物排放标准,其中COD、TP和NH_(3)-N三个指标达到了GB3838—2002《地表水环境质量标准》Ⅳ类水排放标准。 展开更多
关键词 废水处理 倒置A^(2)/o 除磷脱氮 磁混凝沉淀 膜法
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CCL2/CCR2 Contributes to the Altered Excitatory-inhibitory Synaptic Balance in the Nucleus Accumbens Shell Following Peripheral Nerve Injury-induced Neuropathic Pain 被引量:2
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作者 Xiao-Bo Wu Qian Zhu Yong-Jing Gao 《Neuroscience Bulletin》 SCIE CAS CSCD 2021年第7期921-933,共13页
The medium spiny neurons(MSNs)in the nucleus accumbens(NAc)integrate excitatory and inhibitory synaptic inputs and gate motivational and emotional behavior output.Here we report that the relative intensity of excitato... The medium spiny neurons(MSNs)in the nucleus accumbens(NAc)integrate excitatory and inhibitory synaptic inputs and gate motivational and emotional behavior output.Here we report that the relative intensity of excitatory and inhibitory synaptic inputs to MSNs of the NAc shell was decreased in mice with neuropathic pain induced by spinal nerve ligation(SNL).SNL increased the frequency,but not the amplitude of spontaneous inhibitory postsynaptic currents(sIPSCs),and decreased both the frequency and amplitude of spontaneous excitatory postsynaptic currents(sEPSCs)in the MSNs.SNL also decreased the paired-pulse ratio(PPR)of evoked IPSCs but increased the PPR of evoked EPSCs.Moreover,acute bath application of C–C motif chemokine ligand 2(CCL2)increased the frequency and amplitude of sIPSCs and sEPSCs in the MSNs,and especially strengthened the amplitude of N-methyl-D-aspartate receptor(NMDAR)-mediated miniature EPSCs.Further Ccl2 overexpression in the NAc in vivo decreased the peak amplitude of the sEPSC/sIPSC ratio.Finally,Ccr2 knock-down improved the impaired induction of NMDAR-dependent long-term depression(LTD)in the NAc after SNL.These results suggest that CCL2/CCR2 signaling plays a role in the integration of excitatory/inhibitory synaptic transmission and leads to an increase of the LTD induction threshold at the synapses of MSNs during neuropathic pain. 展开更多
关键词 E/I balance Synaptic transmission LTD CCL2 CCR2 Nucleus accumbens Neuropathic pain
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All-transRetinoic Acid Regulates Th1/Th2 Balance in CD4+T cells When GATA-3 is Deficient 被引量:6
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作者 ZHU Yan Feng HU Jia Zhe +2 位作者 ZHAO Pin Nan LIU Lin Xi and LI Yun 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第9期774-777,共4页
The essential effect of vitamin A on immune function occurs through various mechanisms including direct effect on ThloTh2 balance modulation. However, it is unclear whether or not vitamin A can regulate Thl-Th2 balanc... The essential effect of vitamin A on immune function occurs through various mechanisms including direct effect on ThloTh2 balance modulation. However, it is unclear whether or not vitamin A can regulate Thl-Th2 balance under a strong Thl-polarizing condition. Therefore, the purpose of our study was to examine the effect of vitamin A metabolite allotrans retinoic acid (ATRA) on ThloTh2 differentiation in CD4~ T cells under GATA-3 deficiency, which can induce Thl-polarizing condition. In the present study, GATA-3 deficiency T cells were induced by siRNA and checked by real-time quantitative PCR and western blot. GATA-3 deficiency CD4+ T cells and normal CD4+ T were treated for 48 h with or without ATRA. 展开更多
关键词 GATA cell Th All-transRetinoic Acid Regulates Th1/Th2 balance in CD4+T cells When GATA-3 is Deficient CD
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Myricetin alleviates ovalbumin-induced allergic rhinitis in mice by regulating Th1/Th2 balance 被引量:2
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作者 Ya-Nan Shi Jin-Zhu Su +1 位作者 Juan Wang Jiang-Qiao Geng 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2023年第7期306-314,共9页
Objective:To evaluate the effect of myricetin on ovalbumin(OVA)-induced allergic rhinitis in mice.Methods:Mice were sensitized and challenged using OVA(5%,500 mL)intraperitoneally and intranasally,respectively,on an a... Objective:To evaluate the effect of myricetin on ovalbumin(OVA)-induced allergic rhinitis in mice.Methods:Mice were sensitized and challenged using OVA(5%,500 mL)intraperitoneally and intranasally,respectively,on an alternative day for 14 days,followed by administration of myricetin(50,100,and 200 mg/kg)till day 21.Nasal symptoms,biochemical parameters,protein expressions,and histopathology were observed.Results:OVA-induced increased nasal symptoms including rubbing,sneezing,and discharge were significantly reduced by myricetin(100and 200 mg/kg)(P<0.05).Myricetin also protected against histamine challenge and attenuated elevated serum immunoglobulin E(IgE;total and OVA-specific),total IgG1,andβ-hexosaminidase levels,as well as leukotriene C4 and interleukins levels in nasal lavage fluid(P<0.05).Western blot analysis showed that myricetin significantly upregulated the protein expression of T-box expressed in T cells,while downregulating the protein expression of GATA binding protein 3,NF-κB,and IκB-α(P<0.05).Additionally,OVA-induced histopathological abberations in the nasal mucosa was markedly ameliorated by myricetin treatment(P<0.05).Conclusions:Myricetin exerts anti-allergic effects against OVAinduced allergic rhinitis via regulating Th1/Th2 balance. 展开更多
关键词 Allergic rhinitis GATA3 INTERLEUKINS MYRICETIN MoNTELUKAST ovalbumin Th1/Th2 balance
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氮等离子体接枝AA负载Cu_(2)O提高PVDF超滤膜抗污染及自清洁性能
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作者 王雪艳 李茹 《化工新型材料》 北大核心 2025年第6期116-122,128,共8页
采用氮等离子体对聚偏氟乙烯超滤膜(PVDF)表面进行改性,气相接枝丙烯酸(AA),进而负载Cu_(2)O光催化纳米颗粒,以提高膜的抗污染性能和自清洁能力。结果表明:氮等离子体处理的最佳条件为改性时间150s,压强35Pa,射频功率80W,距放电中心40c... 采用氮等离子体对聚偏氟乙烯超滤膜(PVDF)表面进行改性,气相接枝丙烯酸(AA),进而负载Cu_(2)O光催化纳米颗粒,以提高膜的抗污染性能和自清洁能力。结果表明:氮等离子体处理的最佳条件为改性时间150s,压强35Pa,射频功率80W,距放电中心40cm处。接枝丙烯酸后接触角降至65.98°,并为负载Cu_(2)O提供了载体。红外光谱和扫描电镜结果均表明Cu_(2)O负载在PVDF超滤膜表面。负载Cu_(2)O后,PVDF超滤膜(复合膜)纯水通量和牛血清蛋白(BSA)通量均有所提升,截留率由59%提升至85%,污染率由68%降至49.8%。光照30min后,复合膜的纯水通量恢复率为86.19%,远高于原膜的19.82%,具有自清洁性能。 展开更多
关键词 聚偏氟乙烯超滤膜 抗污染 亲水性 Cu_(2)o 自清洁
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水氮耦合对河西灌区滴灌西瓜NH_(3)和N_(2)O排放的影响
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作者 薛亮 马忠明 +3 位作者 赵安宇 罗双龙 薛莲 Muhammad Ali RAZA 《干旱区地理》 北大核心 2025年第5期801-811,共11页
NH_(3)和N_(2)O排放是氮素气态损失的主要途径,研究膜下滴灌条件下不同水氮供应量对氮素气态损失的影响对于河西灌区西瓜生产中水氮管理方案的制定具有重要意义。试验采用裂区设计,主处理按田间持水量的80%(I80)、65%(I65)和50%(I50)设... NH_(3)和N_(2)O排放是氮素气态损失的主要途径,研究膜下滴灌条件下不同水氮供应量对氮素气态损失的影响对于河西灌区西瓜生产中水氮管理方案的制定具有重要意义。试验采用裂区设计,主处理按田间持水量的80%(I80)、65%(I65)和50%(I50)设3个灌水下限,灌水上限设为田间持水量的95%,副处理设0(N0)、100 kg·hm^(-2)(N100)、200 kg·hm^(-2)(N200)和300 kg·hm^(-2)(N300)4个施氮水平。试验采用通气法和静态箱-气相色谱法,分析了不同处理下土壤NH_(3)和N_(2)O排放动态变化以及西瓜产量和品质。结果表明:(1)土壤氮素气态排放受水氮共同影响,NH_(3)、N_(2)O排放在施用基肥后1~2 d达到高峰,持续5~7 d,累积排放量在苗期最大,分别占全生育期的33.33%和47.22%;全生育期NH_(3)、N_(2)O累积排放量分别为3.05~15.39 kg·hm^(-2)和0.51~2.00 kg·hm^(-2)。(2)提高水氮供应量均会促使NH_(3)、N_(2)O排放,氮素的作用大于灌水,I80条件下增施氮肥,NH_(3)、N_(2)O累积排放量分别增加了63.86%~285.48%和120.41%~308.82%。(3)处理I65N200的氮素利用率达到32.62%,显著高于处理I80N300,产量和可溶性固形物含量分别为70159 kg·hm^(-2)和11.39%,与处理I80N300差异不显著。综合考虑产量、品质和氮素利用率,在河西灌区西瓜膜下滴灌种植中,将土壤含水量控制在田间最大持水量的65%~95%之间,施氮量优化至200 kg·hm^(-2)时,能够保持较高的产量和品质,并有利于控制NH_(3)和N_(2)O排放。 展开更多
关键词 西瓜 滴灌 水氮耦合 NH_(3)排放 N_(2)o排放
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A New Material Balance Equation Model for Analyzing Dynamic Performance of C_2 Flooding 被引量:1
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作者 Tian Shubao Zhao Gang 《Petroleum Science》 SCIE CAS CSCD 2006年第2期53-65,共13页
Implementing a CO2 flooding scheme successfully requires the capacity to get accurate information of reservoir dynamic performance and fluids injected. Despite some numerical simulation studies, the complicated drive ... Implementing a CO2 flooding scheme successfully requires the capacity to get accurate information of reservoir dynamic performance and fluids injected. Despite some numerical simulation studies, the complicated drive mechanisms and actual reservoir performance have not been fully understood. There is a strong need to develop models from different perspectives to complement current simulators and provide valuable insights into the reservoir performance during CO2 flooding. The aim of this study is to develop a model by using an improved material balance equation (MBE) to analyze quickly the performance of CO2 flooding. After matching the historical field data the proposed model can be used to evaluate, monitor and predict the overall reservoir dynamic performance during CO2 flooding. In order to account accurately for the complex displacement process involving compositional effect and multiphase flow, the PVT properties and flowability of reservoir fluids are incorporated in the model. This study investigates the effects of a number of factors, such as reservoir pressure, the amount of CO2 injected, the CO2 partition ratios in reservoir fluids, the possibility of the existence of a free CO2 gas cap, the proportion of reservoir fluids contacted with CO2, the starting time of CO2 flooding, oil swelling, and oil flowability improvement by mixing with CO2. The model was used to analyze the CO2 flooding project in Weyburn oil field, Saskatchewan, Canada. This study shows that the proposed model is an effective complementary tool to analyze and monitor the overall reservoir performance during CO2 flooding. 展开更多
关键词 co2 flooding dynamic performance MoNIToRING forecasting material balance
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K_(2) O-PbO-SiO_(2)系古玻璃的复仿制及组成对玻璃结构和性能的影响研究
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作者 赵婷 翟佳豪 +1 位作者 朱建锋 秦毅 《材料导报》 北大核心 2025年第24期52-58,共7页
以碳酸钾(K_(2)CO_(3))、四氧化三铅(Pb_(3)O 4)以及二氧化硅(SiO_(2))为主体原料,氧化铜(CuO)作为着色剂,氟化钙(CaF_(2))作为助熔剂,设计了不同m(SiO_(2))/m(CaO+CaF_(2))比值的玻璃成分。采用熔融-浇注成型法成功实现了K_(2)O-PbO-Si... 以碳酸钾(K_(2)CO_(3))、四氧化三铅(Pb_(3)O 4)以及二氧化硅(SiO_(2))为主体原料,氧化铜(CuO)作为着色剂,氟化钙(CaF_(2))作为助熔剂,设计了不同m(SiO_(2))/m(CaO+CaF_(2))比值的玻璃成分。采用熔融-浇注成型法成功实现了K_(2)O-PbO-SiO_(2)系古代玻璃的复仿制。在此基础上,研究了m(SiO_(2))/m(CaO+CaF_(2))比值保持不变时,CaF_(2)含量对该体系古代玻璃物相组成、网络结构、微观形貌、色度及显微硬度的影响规律;阐明了CaF_(2)在古代玻璃中的作用机制。结果表明,当m(SiO_(2))/m(CaO+CaF_(2))比值为4.252时,复仿制玻璃最接近古代玻璃。在控制比值为4.252不变的基础上,当CaF_(2)含量小于6%(质量分数)时,CaF_(2)充当助熔剂,玻璃呈透明状,且颜色为深蓝色;当CaF_(2)含量大于6%时,Si-O键被破坏,玻璃体系的化学稳定性下降,成核位点增多,析出细小的CaF_(2)晶体,玻璃透光率下降,此时玻璃偏绿色;其硬度随CaF_(2)含量的增加略有降低,从5.0 GPa降低至4.25 GPa。结合优良遮光性、外观颜色及合适的硬度要求,CaF_(2)含量为6%时效果最佳。这对于K_(2)O-PbO-SiO_(2)系古玻璃的科学认知及后续的保护修复具有重要的理论和实践意义。 展开更多
关键词 K_(2)o-Pbo-Sio_(2) 复仿制 氟化钙(CaF_(2)) 古代玻璃 文物保护
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湿化学法制备Cu2O/Cu空心球异质结光催化剂
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作者 贾相华 张辉霞 +1 位作者 刘艳凤 左桂鸿 《无机材料学报》 北大核心 2025年第4期397-404,共8页
窄带隙半导体作为可见光光催化剂,可以有效地将太阳能转化为化学能,在缓解能源短缺和环境污染方面具有潜在的应用前景。以氯化铜(CuCl_(2)·H_(2)O)为前驱体,盐酸羟胺(H_(3)NO·HCl)和硼氢化钠(NaBH_(4))为还原剂,采用一锅无模... 窄带隙半导体作为可见光光催化剂,可以有效地将太阳能转化为化学能,在缓解能源短缺和环境污染方面具有潜在的应用前景。以氯化铜(CuCl_(2)·H_(2)O)为前驱体,盐酸羟胺(H_(3)NO·HCl)和硼氢化钠(NaBH_(4))为还原剂,采用一锅无模板湿化学还原法制备Cu_(2)O/Cu空心球异质结光催化剂。采用不同表征手段对样品形貌、晶体结构、组成、比表面积和光学性质进行分析。加入NaBH_(4)使Cu_(2)O/Cu形貌从中空截角八面体逐渐演化为中空纳米球。通过改变NaBH_(4)加入量可以控制Cu_(2)O表面Cu层厚度。NaBH_(4)直接还原Cu_(2)O使Cu_(2)O和Cu界面紧密结合,这有利于载流子分离和传输,Cu的表面等离子体共振(SPR)效应使Cu_(2)O/Cu对可见光的吸收能力增强,因此Cu_(2)O/Cu对甲基橙(MO)和无色恩诺沙星(ENR)均表现出良好的光催化活性。连续循环使用5次,Cu_(2)O/Cu对MO的降解率影响不大。捕获实验表明·O_(2)^(-)和空穴是降解MO过程中主要的活性物质。Cu_(2)O/Cu的良好光催化活性归因于Cu_(2)O和Cu的协同作用。本研究为异质结光催化剂的制备提供了一种策略。 展开更多
关键词 Cu2o/Cu异质结 纳米空心球 光催化 Cu层厚度
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Construction of a Pillared-layer Framework Based on Charge Balance:CO2 Adsorption and Luminescence 被引量:5
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作者 傅红如 朱林 +2 位作者 王凯路 王慧芳 韩民乐 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第3期461-466,共6页
Via the strategy of charge balance,one new pillared layered metal-organic framework [Zn2(TNB)(2-nim)](H3TNB = 4,4?,4??-nitrilotribenzoicacid,2-nim = 2-nitroimidazole)(1) was successfully synthesized based o... Via the strategy of charge balance,one new pillared layered metal-organic framework [Zn2(TNB)(2-nim)](H3TNB = 4,4?,4??-nitrilotribenzoicacid,2-nim = 2-nitroimidazole)(1) was successfully synthesized based on mixed ligands,where binuclear [Zn2(CO2)3]~+ cluster-based cationic layers [Zn2(TNB)]~+ are connected by deprotonated 2-nitroimidazole.Meanwhile,CO2 adsorption bahaviors and luminescent property of compound 1 were investigated. 展开更多
关键词 pillared-layer metal-organic frameworks charge balance co2 adsorption luminescence
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黄河上游梯级水库N_(2)O溶存浓度、扩散通量时空特征及其生物与非生物影响因素
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作者 黄山 吴艺 +7 位作者 毛旭锋 金鑫 金彦香 杜凯 唐文家 于红妍 肖锋 季海川 《盐湖研究》 2025年第3期46-53,共8页
水库是氧化亚氮(N_(2)O)排放的重要场所,近年来其排放量急剧增加。但N_(2)O在梯级水库中的排放和微生物基础研究相对缺乏。在2023年5月(枯水期)和8月(丰水期)使用顶空平衡一气相色谱和扩散模型法对黄河上游10座梯级水库N_(2)O溶存浓度... 水库是氧化亚氮(N_(2)O)排放的重要场所,近年来其排放量急剧增加。但N_(2)O在梯级水库中的排放和微生物基础研究相对缺乏。在2023年5月(枯水期)和8月(丰水期)使用顶空平衡一气相色谱和扩散模型法对黄河上游10座梯级水库N_(2)O溶存浓度和扩散通量进行研究,采用Illumina高通量测序分析沉积物nirS型反硝化细菌群落特征,利用皮尔逊(Pearson)相关性探究N_(2)O溶存浓度、扩散通量对生物/非生物因素的响应。结果表明,(1)黄河梯级水库N_(2)O溶存浓度(7.87~35.68 nmol/L)和扩散通量(156.53~610.31 nmol(/m^(2)·h))存在显著的时空差异(p<0.05),表现为大气N_(2)O的源。(2)沉积物nirS型反硝化细菌相对丰度前3的菌属分别为副球菌属(Paracoccus,0.90%~10.94%)、罗河杆菌属(Rhodanobacter,0.01%~7.75%)和假单胞菌属(Pseudomonas,0%~20.24%)。不同水文时期群落组成差异不显著(p>0.05)。(3)脱氯单胞菌属(Dechloromonas)、固氮弓菌属(Azoarcus)和Sulfuritalea是参与黄河梯级水库N_(2)O产生的关键菌属。水温、溶解氧、电导率、风速和alpha多样性是影响黄河梯级水库N_(2)O溶存浓度和扩散通量的关键因素。 展开更多
关键词 青藏高原 N_(2)o nirS 反硝化细菌 沉积物
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