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柚皮苷对哮喘模型小鼠气道炎症细胞凋亡的促进作用及其机制

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世界科学技术-中医药现代化 2024年第3期26卷 742-750页

作者：胥彦琪郭永梅高建华江西医学高等专科学校药学院上饶334000 江西医学高等专科学校医学技术学院上饶334000

目的探讨柚皮苷对哮喘模型小鼠气道炎症细胞凋亡的调节作用及其与苦味受体(Tas2rs)的关系。方法36只BALB/c小鼠随机分为6组(n=6):空白对照组、卵清蛋白模型组(OVA)、地塞米松组(10 mg·kg^(-1),阳性对照药物)、柚皮苷低、中、高剂量组(1... 详细信息

目的探讨柚皮苷对哮喘模型小鼠气道炎症细胞凋亡的调节作用及其与苦味受体(Tas2rs)的关系。方法36只BALB/c小鼠随机分为6组(n=6):空白对照组、卵清蛋白模型组(OVA)、地塞米松组(10 mg·kg^(-1),阳性对照药物)、柚皮苷低、中、高剂量组(10、20、40 mg·kg^(-1))。除空白对照组外,各组小鼠均采用OVA诱导气道哮喘。溶媒、地塞米松或柚皮苷连续灌胃6天,测定小鼠呼吸功能及肺泡灌洗液细胞数量,观察小鼠肺及气道形态,测定呼吸系统阻力(Rrs)、肺的弹性阻力(Ers)和呼吸顺应性(Crs),测定肺组织相关促凋亡因子mRNA表达水平,测定Tas2rs及其下游基因mRNA表达水平。结果与OVA模型组比较,柚皮苷可以剂量依赖性降低Rrs和Ers,增加Crs,降低白细胞、嗜酸性粒细胞、淋巴细胞和中性粒细胞数量;与OVA模型组比较,柚皮苷高剂量组小鼠肺组织炎性细胞浸润显著减少,肺、气道组织的Tas2r108、Tas2r135和Tas2r143及其下游靶基因α-gust和Trpm5的mRNA表达水平显著降低,促凋亡因子P53、Bax和Casp3的mRNA表达水平均增加,而凋亡抑制因子Bcl2的mRNA表达水平降低。结论柚皮苷预防性给药可促进哮喘小鼠气道Tas2rs信号活化,降低气道炎性细胞数量,减轻气道损伤。柚皮苷作为Tas2rs激动剂可作为潜在的抗哮喘药物进行开发。

关键词：柚皮苷苦味受体哮喘炎性细胞凋亡

超稳激光频率锁定系统中干涉效应抑制与锁频电路设计

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中国激光 2024年第7期51卷 241-249页

作者：肖锐晏北飞蔡桢荻方鹏程徐晏琪王艳孙焕尧陈群峰中国科学院精密测量科学与技术创新研究院波谱与原子分子物理国家重点实验室湖北武汉430071 中国科学院大学北京100049

超稳激光是精密测量领域的关键工具,其频率稳定度很大程度上取决于频率锁定稳定度。笔者理论研究了干涉效应对锁频误差信号的影响,并通过实验研究了降低干涉效应的方法,以提高激光的频率锁定稳定度。经过优化后,锁频系统的锁定稳定度相... 详细信息

超稳激光是精密测量领域的关键工具,其频率稳定度很大程度上取决于频率锁定稳定度。笔者理论研究了干涉效应对锁频误差信号的影响,并通过实验研究了降低干涉效应的方法,以提高激光的频率锁定稳定度。经过优化后,锁频系统的锁定稳定度相对于参考腔线宽达到了9×10^(-7)。在参考腔线宽为21 kHz(精细度为7.5万)的情况下,将1.5μm激光的频率稳定度锁定到4.0×10^(-16)水平,接近10 cm参考腔的热噪声极限。本文所提降低干涉效应的方法是研制稳定度高达10^(-17)水平的超稳激光器的重要参考。

关键词：激光器激光稳定 Pound‒Drever‒Hall稳频干涉效应超稳腔超稳激光

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一种用于超稳激光的数字控制锁频电路

中国激光 2024年第13期51卷 66-72页

作者：晏北飞肖锐蔡桢荻周义辰方鹏程徐晏琪王艳孙焕尧陈群峰中国科学院精密测量科学与技术创新研究院波谱与原子分子物理国家重点实验室湖北武汉430071 中国科学院大学北京100049

超稳激光具有超高的频率稳定度和极窄线宽等优点,广泛应用于各种精密测量物理实验。为了确保不引入额外开关噪声,其频率锁定电路通常采用模拟电路实现,但是模拟控制电路存在锁定参数调节不方便、难以实现自动锁定和远程控制等方面的不... 详细信息

超稳激光具有超高的频率稳定度和极窄线宽等优点,广泛应用于各种精密测量物理实验。为了确保不引入额外开关噪声,其频率锁定电路通常采用模拟电路实现,但是模拟控制电路存在锁定参数调节不方便、难以实现自动锁定和远程控制等方面的不足。针对这些问题,提出一种基于数字控制的通用型模拟锁频电路。该电路可以通过数字开关实现对锁定参数的大范围调节,通过数字算法实现自动重锁,同时该电路具有USB通信功能,可以通过电脑远程调整锁频参数和实现频率锁定。利用该电路实现了激光器频率到高精细光学谐振腔的长期锁定,锁定后激光频率稳定度1 s积分时间4.6×10^(-16),2~10 s积分时间小于4.2×10^(-16),接近10 cm超稳腔的热噪声极限。这种长期稳定运行的超稳激光系统将有利于基于超稳激光的精密测量物理实验的开展和光钟走向应用。

关键词：超稳激光 Pound-Drever-Hall稳频数字控制锁频电路自动重锁

Tuning the selectivity of photoreduction of CO2 to syngas over Pd/layered double hydroxide nanosheets under visible light up to 600 nm

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Journal of Energy Chemistry 2020年第7期29卷 1-7,I0001页

作者： Xian Wang Zelin Wang Ya Bai Ling Tan yanqi xu Xiaojie Hao Jikang Wang Abdul Hanif Mahadi Yufei Zhao Lirong Zheng Yu-Fei Song State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Institute of High Energy Physics The Chinese Academy of SciencesBeijing 100049China Centre for Advanced Material and Energy Sciences Universiti Brunei DarussalamTungku LinkGadong BE1410Brunei Darussalam

Photocatalytic reduction of CO2 with H2 O to syngas is an effective way for producing high value-added chemical feedstocks such as methanol and light olefins in ***,the precise control of CO/H2 ratio from photocatalytic CO2 reduction reaction still poses a great challenge for the further ***,we prepared a series of highly efficient heterostructure based on highly dispersed palladium supported on ultrathin Co Al-layered double hydroxide(LDH).In conjunction with a Ru-complex sensitizer,the molar ratios of CO/H2 can be tuned from 1:0.74 to 1:3 under visible-light irradiation(λ>400 nm).More interestingly,the syngas can be obtained under light irradiation atλ>600 *** characterization and density functional theory calculations revealed that the remarkable catalytic activity can be due to the supported palladium,which improved the charge transfer ***,more H atoms were used to generate H2 on the supported palladium for further tunable CO/H2 *** work demonstrates a new strategy for harnessing abundant solar-energy to produce syngas from a CO2 feedstock.

关键词： Syngas CO2 reduction Layered double hydroxide Visible light

Transfer of laser frequency from 729 nm to 1.5 μm with precision at the level of 10^(−20)

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Chinese Optics Letters 2022年第8期20卷 54-58页

作者： Pengcheng Fang Huanyao Sun Yan Wang yanqi xu Qunfeng Chen State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

By using a self-reference transfer oscillator method,two individual 1560 nm lasers with about 1.2 GHz frequency difference were phase locked to a 729 nm ultra-stable laser at two preset *** measuring the beat frequency of the two 1560 nm lasers,fractional instabilities of 2×10^(−17) at 1 s and 2×10^(−20) at 10,000 s averaging time were obtained,and the relative offset compared with the theoretical value was 4.2×10^(−21)±4.5×10^(−20).The frequency ratio of them was evaluated to a level of 1.3×10^(−20) in one day’s data *** work was a preparation for remote comparison of optical clocks through optical fiber *** technique can also be used to synthesize ultra-stable lasers at other wavelengths.

关键词： optical frequency transfer optical clock comparison optical frequency comb

亲水剂加料方式对水性聚氨酯胶粘剂性能的影响

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中国皮革 2014年第18期43卷 119-121页

作者：徐燕奇中科华宇(福建)科技发展有限公司福建莆田351139

固定水性聚氨酯鞋胶配料比例和操作工艺条件,仅改变亲水剂DMPA(二羟甲基丙酸)的加料时间,制备出不同水性聚氨酯鞋胶样品,分别测定各样品的初粘性和剥离强度,分析比较DMPA加料时间对样品粘接性能的影响,确定较佳的DMPA加料方式。

关键词：加料方式水性聚氨酯鞋胶粘接性能

Structure design and catalytic performance of LDH based materials

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Structure design and catalytic performance of LDH based mate...

Adenosine triphosphate mediates the pain tolerance effect of manual acupuncture at Zusanli(ST36) in mice

中国化学会第十届全国无机化学学术会议

作者： Zelin Wang Ling Tan yanqi xu Yufei Zhao Yu-Fei Song State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

Layered double hydroxide(LDHs) represent an important class of 2D layered materials with the general formula of [MM(OH)](A)x/n·mHO. Compared with other oxides(hydroxides), LDHs show the advantage of tunable chemical composition, thickness, and precursors of metal oxides, thereby can be widely used as electrocatalysts, photocatalysts and thermocatalysts. Recently, our group investigated the unique structure and applications of LDHs.(1). We reported a facile one-step method to synthesize single Ru atoms supported on a monolayer NiFe-layered double hydroxide(denoted as Ru/mono-NiFe). Through XAFS, STEM and DFT calculation, we have demonstrated that the single Ru atoms are not dispersed randomly in the LDH structure but are uniquely located on the top of the Fe-metal atom of mono-NiFe via three oxygen atoms. (2). We reported a heterogeneous photocatalyst system that consists of ruthenium complex and monolayer NiAl-LDH, which act as light-harvesting and catalytic units for selective photoreduction of CO and HO into CH and CO, the selectivity of CH is 70.3%, and the H evolution reaction can be completely suppressed under irradiation with λ > 600 nm. (3). Topological transformation of layered double hydroxides(LDHs) to the corresponding mixed metal oxides(MMOs) offers an efficient strategy to achieve such interfaces. We reported a detailed investigation of the topological transformation of LDHs. The as-prepared MMO with abundant interfaces can be modulated by calcination of ZnCo-LDH at different temperatures. Among them, the ZnCo-LDH calcinated at 200 °C revealed the most abundant interfaces and exhibits excellent performance in electrochemical water oxidation.

关键词： layered double hydroxide topological transformation heterogeneous catalysts

来源： cnki会议评论

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Journal of Traditional Chinese Medicine 2024年第4期44卷 660-669页

作者： LI Zhongzheng ZHAO Yadan Ma Weigang Zhang Yonglong xu Zhifang XI Qiang LI yanqi QIN Siru ZHANG Zichen WANG Songtao ZHAO xue LIU Yangyang GUO Yi GUO Yongming Research Center of Experimental Acupuncture Science Tianjin University of Traditional Chinese MedicineTianjin 301617China National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion Tianjin 301617China Department of Acupuncture and Moxibustion Qingdao Hiser Hospital Affiliated of Qingdao University(Qingdao Traditional Chinese Medicine Hospital)Qingdao 266033China School of Traditional Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China School of Acupuncture and Moxibustion and Tuina Tianjin University of Traditional Chinese MedicineTianjin 301617China

OBJECTIVE:To investigate the mechanisms behind the effects of acupuncture in Traditional Chinese Medicine,we delved into the adenosine triphosphate/peripheral purinergic P2X receptor 3(ATP/P2X3)receptor signaling system as an indicator of the body's energy state,commonly referred to as"Qi".METHODS:The tail-flick test was utilized to explore the impact of acupuncture on pain tolerance threshold(PTT)in mice,while also assessing adenosine(ADO)levels and adenylate energy charge(EC)at Zusanli(ST36).The study further investigated the dose-dependent effects of acupuncture on PTT and ADO levels at Zusanli(ST36).To shed light on the underlying mechanisms of acupuncture's effects,the study examined the impact of ATP,a P2X3 receptor antagonist,and adenosine disodium on PTT following acupuncture ***:Acupuncture at Zusanli(ST36)led to significant improvements in PTT in mice,with the most effective interventions being twirling for 2 min and needle retention for 28 *** interventions also resulted in significant increases in ATP *** effects of acupuncture were further augmented by administration of different doses of ATP at Zusanli(ST36),and pretreatment with a P2X3 receptor antagonist decreased *** EC peaked at 30 min after intraperitoneal injection of ATP,and pretreatment with various doses of *** 30 min prior to acupuncture increased PTT in a dose-dependent ***,pretreatment with an *** intramuscular injection of adenosine disodium enhanced the effects of ***:This research provides compelling evidence that ATP is involved in the regulation of PTT through acupuncture,revealing new avenues for achieving enhanced clinical outcomes.

关键词： acupuncture point ST36(Zusanli) adenosine triphosphate receptors,purinergic P2X3 energy state

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触粘性——鞋大底胶被忽略的重要特性

中国胶粘剂 2014年第11期23卷 44-47页

作者：徐燕奇许莹中科华宇(福建)科技发展有限公司福建莆田351139 中科院福建物质结构研究所福建福州350002

介绍了鞋用胶现行标准的相关要求,综述了鞋大底胶的触粘性在制鞋生产中的重要性、与现有标准中初粘力的区别以及相应的测定方法。最后阐述了在鞋用胶标准中增加触粘性限定要求的必要性。

关键词：鞋用胶鞋大底胶触粘性初粘力粘接性能