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Toward high performance microwave absorber by implanting La_(0.8)CoO_(3)nanoparticles on rGO

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Journal of Materials Science & Technology 2024年第7期174卷 176-187页

作者： li Chang yu-Ze Wang Xin-Ci Zhang lin li Hua-Zhang Zhai Mao-Sheng Cao Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics&Electronic EngineeringHarbin Normal UniversityHarbin 150025China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China

The advent of“intelligent era”brings our life more convenience,but the electromagnetic radiation sur-rounding us not only greatly threatens human health,also makes information leakage and hidden trouble to national defense ***,it is very urgent to develop novel electromagnetic wave absorption materials with lightweight,strong absorption,tunable absorption frequency and broad band ***,a novel electromagnetic wave absorber is obtained by constructing La_(0.8)CoO_(3)-rGO nanocompos-ite,where La_(0.8)CoO_(3)nanoparticles are anchored on graphene nanosheets by the electrostatic interaction between GO and La_(0.8)CoO_(3).The effect of hybridization ratio of La_(0.8)CoO_(3)and rGO on microwave ab-sorption properties is carefully *** optimal reflection loss of La_(0.8)CoO_(3)-rGO nanocomposite can reach-62.34 dB with the maximum effective bandwidth of 6.08 GHz,presenting 48.78%and 245.45%increment compared to bare La_(0.8)CoO_(3)nanoparticles,*** effective absorption bandwidth covers a broad electromagnetic wave absorption band from Ku band to the C band by tailoring thickness of the absorbers from 2.4 mm to 4.4 *** fascinating electromagnetic wave absorption performance is attributed to the synergy effect of La_(0.8)CoO_(3)and rGO,which integrates magnetic and dielectric loss caused by resonance,conductance,relaxation,and scattering *** result confirms that La_(0.8)CoO_(3)-rGO nanocomposite is potential candidates toward high-efficiency microwave absorbers and provides a valuable pathway for designing high-performance microwave attenuation materials in the future.

关键词： Perovskite La_(0.8)CoO_(3)nanoparticles Graphene Nanocomposite Microwave absorbing Broad band absorption

Sequential reactant water management by complementary multisite catalysts for surpassing platinum hydrogen evolution activity

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Nano Research 2024年第3期17卷 1232-1241页

作者： yu lin Defang Ding Shicheng Zhu Qunlei Wen Huangjingwei li Zhen li Youwen liu Yi Shen China Engineering Research Center of Nano-Geomaterials of Ministry of Education Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430078China State Key Laboratory of Materials Processing and Die&Mould Technology and School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Alkaline hydrogen evolution reaction(HER)offers a near-zero-emission approach to advance hydrogen ***,the activity limited by the multiple reaction steps involving H_(2)O molecules transfer,absorption,and activation still unqualified the thresholds of economic ***,we proposed a multisite complementary strategy that incorporates hydrophilic Mo and electrophilic V into Ni-based catalysts to divide the distinct steps on atomically dispersive sites and thus realize sequential regulation of the HER *** Isotopic labeled in situ Raman spectroscopy describes 4-coordinated hydrogen bonded H_(2)O to be free H_(2)O passing the inner Helmholtz plane in the vicinity of the catalysts under the action of hydrophilic Mo ***,potential-dependent electrochemical impedance spectroscopy(EIS)reveals that electrophilic V sites with abundant 3d empty orbitals could activate the lone-pair electrons in the free H_(2)O molecules to produce more protic hydrogen,and dimerize into H_(2) at the Ni *** the sequential management of reactive H_(2)O molecules,NiMoV oxides multisite catalysts surpass Pt/C hydrogen evolution activity(49 mV@10 mA∙cm^(-2) over 140 h).Profoundly,this study provides a tangible model to deepen the comprehension of the catalyst–electrolyte interface and create efficient catalysts for diverse reactions.

关键词： hydrogen evolution activity complementary multisite catalysts sequential reactive water management interfacial water molecules

A novel dandelion-based bionic proppant and its transportation mechanism in different types of fractures

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Petroleum Science 2024年第4期21卷 2583-2599页

作者： Jun li Ming-Yi Wu Xu Han Si-yuan He Ze-yu lin State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Sichuan Particles Energy and Technology Co. Ltd Chongqing Industry Polytechnic College Petroleum Systems Engineering Faculty of Engineering and Applied Science University of Regina

Low-permeability reservoirs are generally characterized by low porosity and low permeability. Obtaining high production using the traditional method is technologically challenging because it yields a low reservoir recovery factor. In recent years, hydraulic fracturing technology is widely applied for efficiently exploiting and developing low-permeability reservoirs using a low-viscosity fluid as a fracturing ***, the transportation of the proppant is inefficient in the low-viscosity fluid, and the proppant has a low piling-up height in fracture channels. These key challenges restrict the fluid(natural gas or oil) flow in fracture channels and their functional flow areas, reducing the profits of hydrocarbon *** study aimed to explore and develop a novel dandelion-bionic proppant by modifying the surface of the proppant and the fiber. Its structure was similar to that of dandelion seeds, and it had high transport and stacking efficiency in low-viscosity liquids compared with the traditional ***, the transportation efficiency of this newly developed proppant was investigated experimentally using six different types of fracture models(tortuous fracture model, rough fracture model,narrow fracture model, complex fracture model, large-scale single fracture model, and small-scale single fracture model). Experimental results indicated that, compared with the traditional proppant, the transportation efficiency and the packing area of the dandelion-based bionic proppant significantly improved in tap water or low-viscosity fluid. Compared with the traditional proppant, the dandelionbased bionic proppant had 0.1-4 times longer transportation length, 0.3-5 times higher piling-up height, and 2-10 times larger placement area. The newly developed proppant also had some other extraordinary features. The tortuosity of the fracture did not influence the transportation of the novel proppant. This proppant could easily enter the branch fracture and n

关键词： Dandelion-based bionic proppant Low-viscosity fracturing fluid Unconventional reservoir Volumetric fracturing stimulation

TOTAL SYNTHESIS OF(-)-3-OXOEUDESMA-1,4,11(13)-TRIEN-7αH-12-OIC ACID

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Chinese Chemical Letters 1993年第2期4卷 105-106页

作者： yu lin li Xin CHEN Si Chang SHAO Tong Shuang li State Key Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry Lanzhou UniversityLanzhou 730000.

The first total synthesis of(-)-3-oxoeudesma-1,4,11(13)-trien-7αH-12-oic acid 1 has been *** key step is one-pot reaction involving dehydrogenation and allylic oxidation with selenium dioxide.

关键词： TOTAL SYNTHESIS OF EIMS H-12-OIC ACID OXOEUDESMA-1,4,11 TRIEN-7

Synthetic Studies on Diarylheptanoids──Syntheses of 1,7-Bis(4-Hydroxyphenyl)-1,4,6-Heptatriene-3-One and Acetogenin G

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Chinese Chemical Letters 1997年第4期8卷 291-292页

作者： Shi Jun DA Ying li Chu Sheng HUANG Xiao Hong li and yu lin li(National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry, LanZhou University, Lanzhou 730000) NATL LAB APPL ORGAN CHEM LANZHOU 730000PEOPLES R CHINA LANZHOU UNIV INST ORGAN CHEMLANZHOU 730000PEOPLES R CHINA

The two new diarylheptanoids, 1,7-bis(4-hydroxyphenyl)-1,4,6 (l) and aecrogenin G (2) were Synthesized starting from 4-hydroxybenzaldehyde (3) and acetone

关键词： Hydroxyphenyl Syntheses of 1,7-Bis Synthetic Studies on Diarylheptanoids Heptatriene-3-One and Acetogenin G

Macrophage CARD9 mediates cardiac injury following myocardial infarction through regulation of lipocalin 2 expression

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Signal Transduction and Targeted Therapy 2023年第11期8卷 5383-5393页

作者： Yan liu Yi-hui Shao Jun-meng Zhang Ying Wang Mei Zhou Hui-qin li Cong-cong Zhang Pei-jie yu Shi-juan Gao Xue-rui Wang li-xin Jia Chun-mei Piao Jie Du yu-lin li Beijing Anzhen Hospital Capital Medical UniversityThe Key Laboratory of Remodeling-Related Cardiovascular DiseasesMinistry of EducationBeijing Collaborative Innovative Research Center for Cardiovascular DiseasesBeijing Institute of Heart Lung and Blood Vessel DiseasesBeijing100029China

Immune cell infiltration in response to myocyte death regulates extracellular matrix remodeling and scar formation after myocardial infarction(MI).Caspase-recruitment domain family member 9(CARD9)acts as an adapter that mediates the transduction of pro-inflammatory signaling cascades in innate immunity;however,its role in cardiac injury and repair post-MI remains *** found that Card9 was one of the most upregulated Card genes in the ischemic myocardium of ***9 expression increased considerably 1 day post-MI and declined by day 7 ***,CARD9 was mainly expressed in F4/80-positive ***9 knockout(KO)led to left ventricular function improvement and infarct scar size reduction in mice 28 days ***,Card9 KO suppressed cardiomyocyte apoptosis in the border region and attenuated matrix metalloproteinase(MMP)*** sequencing revealed that Card9 KO significantly suppressed lipocalin 2(Lcn2)expression *** LCN2 and the receptor solute carrier family 22 member 17(SL22A17)were detected in ***,we demonstrated that Card9 overexpression increased LCN2 expression,while Card9 KO inhibited necrotic cell-induced LCN2 upregulation in macrophages,likely through NF-κ***2 KO showed beneficial effects post-MI,and recombinant LCN2 diminished the protective effects of Card9 KO in ***2 KO reduced MMP9 post-MI,and Lcn2 overexpression increased Mmp9 expression in ***22a17 knockdown in macrophages reduced MMP9 release with recombinant LCN2 *** conclusion,our results demonstrate that macrophage CARD9 mediates the deterioration of cardiac function and adverse remodeling post-MI via LCN2.

关键词： CARD9 protective immunity

Regioselective Synthesis of Two Novel 4-alkenyloxy-2,6-dihydroxyacetophenones

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Chinese Chemical Letters 1998年第9期9卷 799-800页

作者： Chu Sheng HUANG Zhe ZHANG Shu Hua li yu lin li (National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry, Lanzhou University, Lanzhou 730000) Lanzhou Univ Inst Organ Chem Lanzhou 730000 Peoples R China Lanzhou Univ Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China

Two novel Acetophenones, 4-(1'-geranyloxy)-2,6-dihydroxyacetophenone 1 and 4-(1'-farnesyl)-2,6-dihydroxyacetophenone 2 isolated from the fruit of Evodia merrillii and from the aerial parts of Borronia ramosa respectiv... 详细信息

关键词： 4-alkenyl-2 6-dihydroxyacetophenones total synthesis

STUDIES ON THE PRENYLFLAVONOIDS PART Ⅳ^([1]). SYNTHESIS OF(±)LESPEDEZAFLAVANONEE

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Chinese Chemical Letters 1993年第5期4卷 393-394页

作者： Fang Jie ZHANG lian yun ZHAO yu lin li State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhon 730000

(±)Lespedezaflavanone E, 6, 8, 3'-tri (γ,γ-dimethylallyl)-5, 7, 2', 4'-tetrahydroxy-flavanone, has been synthesized by the condensation of 3, 5-di (γ,γ-dimethylallyl)-4, 6-dimethoxymethoxy-2-hydroxyacetophenone a... 详细信息

关键词： ppm OH LESPEDEZAFLAVANONEE STUDIES ON THE PRENYLFLAVONOIDS PART SYNTHESIS OF

Investigation on occupant presence and appliance operation schedules for university campus in south China sub-tropical area

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Building Simulation 2024年第2期17卷 301-318页

作者： Siwei Lou Zhongyuan lin yukai Zou Dawei Xia yu Huang Zhuohong li Zhaowen Gu School of Civil Engineering Guangzhou UniversityGuangzhou Higher Edu.Mega CenterGuangzhouChina School of Architecture and Urban Planning Guangzhou UniversityGuangzhou Higher Edu.Mega CenterGuangzhouChina

Building occupant presence during varying periods is crucial to the performance studies of buildings and city ***,the understanding of the building occupancies on the university campus remains *** address this gap,our study employs field measurements,payment records,course arrangements,and building access systems to depict the occupancy patterns of the canteen,dormitory,library,and teaching and lab buildings during weekdays and *** found that the occupancy rates across different buildings are somehow interrelated,given that the total number of occupants on campus is generally ***,dormitory occupancy rates tend to be low during the morning and afternoon course hours,which inversely correlates with the high occupancy rates in the teaching and lab buildings during these ***,canteens experience surges in occupancy during meal times,which coincide with a decrease in library ***,we established appliance operation schedules for dormitories through surveys and on-site *** dispensers and electronic devices were identified as the primary energy consumers for both male and female occupants,with desk-top fans and hairdryers being significant energy users for male and female occupants,*** findings are essential for energy studies within a campus setting,underlining the importance of considering occupant behaviors on a regional scale.

关键词： building occupant behavior university campus occupancy schedule appliance operation schedule