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Effects of Atmospheric Pressure on Developmental characteristics and the stability of Air Entraining Agent for concrete

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Journal of Wuhan University of Technology(Materials science) 2024年第4期39卷 979-989页

作者：李立辉牛开民 TIAN Bo cHEN Xin fu Ziqian ZHU Xuwei school of civil Engineering Chongqing Jiaotong UniversityChongqing 400074China Transportation science and Engineering Harbin Institute of TechnologyHarbin 150090China Research Institute of Highway Ministry of TransportBeijing 100088China

In order to ascertain the effects of atmospheric pressure on developmental characteristics and the stability of AEA(air-entraining agent)solution bubbles,AEA solution experiments and AEA solution bubble experiments were,respectively,conducted in Peking(50 m,101.2 kPa)and Lhasa(3,650 m,63.1 kPa).surface tensions and inflection-point concentrations were tested based on AEA solutions,whilst developmental characteristics,thicknesses and elastic coefficients of liquid films were tested based on air bubbles of AEA *** study involved three types of AEAs,which were TM-O,226A,and *** experimental results show that initial sizes of TM-O,226A,and 226s are,respectively,increased by 43.5%,17.5%,and 3.8%.With the decrease of ambient pressure,the drainage rate and the drainage index of AEA solution bubbles *** experiments show that the liquid film thicknesses of all tested AEA solution bubbles are in micron *** the atmospheric pressure decreases from 101.2 to 63.1 kPa,the liquid film thicknesses of three types of AEA solutions decrease in various degrees;and film elasticities at critical thicknesses *** film of 226s solution bubbles is the most stable,presenting as a minimum thickness *** should be noted that elastic coefficient of liquid film only represents the level at critical thickness,thus it can not be applied as the only evaluating indicator of bubble *** a type of AEA,factors affecting the stability of its bubbles under low atmospheric pressure include initial bubbles size,liquid film thickness,liquid film elasticity,ambient temperature,etc.

关键词： air-entraining agent surface tension bubble size liquid film thickness liquid film elasticity atmospheric pressure

soil bacterial and fungal communities resilience to long-term nitrogen addition in subtropical forests in china

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Journal of Forestry Research 2024年第2期35卷 95-108页

作者： Xinlei fu Yunze Dai Jun cui Pengfei Deng Wei Fan Xiaoniu Xu school of Forestry and Landscape Architecture Anhui Agricultural UniversityHefei 230036AnhuiPeople’s Republic of China suzhou Polytechnic Institute of Agriculture Suzhou 215008JiangsuPeople’s Republic of China college of Life and Environment sciences Huangshan UniversityHuangshan 245041AnhuiPeople’s Republic of China

Atmospheric nitrogen(N)deposition is predicted to increase,especially in the ***,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have not been clarified.A long-term nutrient addition experiment was conducted in a subtropical evergreen old-growth forest in *** four treatments were:control,low N(50 kg N ha^(-1)a^(-1)),high N(100 kg N ha^(-1)a^(-1)),and combined N and phosphorus(P)(100 kg N ha^(-1)a^(-1)+50 kg P ha^(-1)a^(-1)).Metagenomic sequencing characterized diversity and composition of soil microbial communities and used to construct bacterial/fungal co-occurrence ***-treated soils were more acidic and had higher levels of dissolved organic carbon than *** were no significant differences in microbial diversity and community composition across *** addition of nutrients increased the abundance of copiotrophic bacteria and potentially beneficial microorganisms(e.g.,Gemmatimonadetes,chaetomium,and Aureobasidium).Low N addition increased microbiome network *** rare fungi were identified as module hubs under nutrient addition,indicating that low abundance fungi were more sensitive to increased *** results indicate that the overall composition of microbial communities was stable but not static to long-term N *** findings provide new insights that can aid predictions of the response of soil microbial communities to long-term N addition.

关键词： Long-term nitrogen addition Old-growth subtropical forest Metagenomics Beneficial microorganisms co-occurrence network

Novel Hf_(x)Ta_(1−x)c solid solution nanowire toughened Hfc coating:An effective strategy for synchronous enhanced mechanical and anti-ablation performance

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Journal of Advanced ceramics 2024年第5期13卷 590-601页

作者： Hui chen Yulei Zhang Yanqin fu Wenhan Gai Junhao Zhao Haohui Zhang shaanxi Key Laboratory of Fiber Reinforced Light composite Materials Northwestern Polytechnical UniversityXi’an 710072China Henan Key Laboratory of High Performance carbon Fiber Reinforced composites Institute of Carbon Matrix CompositesHenan Academy of SciencesZhengzhou 450046China

Ultra-high-temperature ceramic nanowires have shown increasing potential for use as thermal structural ***,novel single-crystal Hf_(0.5)Ta_(0.5)c solid solution nanowires were synthesized and incorporated with a Hfc coating to construct a robust structure with Hf_(0.5)Ta_(0.5)c solid solution nanowires uniformly distributed and interconnected within the *** novel Hf_(0.5)Ta_(0.5)c solid solution nanowires could effectively hinder crack propagation through crack tip pinning and crack *** mechanism substantially enhanced the elastic modulus and fracture toughness of the Hfc coating by 53.29%and 59.67%,*** toughened Hfc coating displayed superior fracture toughness and good interfacial binding strength with the substrate to resist severe oxidation and ***,the high thermal conductivity of the toughened Hfc coating promoted heat ***,in comparison to the pure Hfc coating,the toughened Hfc coating displayed smaller mass and linear ablation rates of−0.35 mg·s^(−1)and−0.46μm·s^(−1),which decreased by 39.66%and 36.98%,*** work not only simultaneously enhances the mechanical properties and ablation resistance of Hfc-coated carbon/carbon(c/c)composites but also provides novel prospects for advanced ultrahigh-temperature ceramic nanowires under extreme conditions.

关键词： Hf_(x)Ta_(1−x)c solid solution nanowires Hfc coating carbon/carbon(c/c)composites mechanical performance ablationresistance

Porous s-doped carbon nitride foam with accelerated charge dynamics for synchronous photocatalytic hydrogen production and highly selective oxidation of amines

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Nano Research 2024年第8期17卷 6860-6869页

作者： Yu He Aiping Wu Nan Wang Ying Xie chungui Tian Honggang fu Key Laboratory of functional Inorganic Material chemistry(Ministry of Education of the People’s Republic of china) Heilongjiang UniversityHarbin 150080China

Photocatalytic hydrogen evolution coupled with organic oxidation holds great promise for converting solar energy into high-valueadded chemicals,but it is hampered by sluggish charge dynamics and limited redox ***,a porous s-doped carbon nitride(s-c_(3)N_(4−y))foam assembled from ultrathin nanosheets with rich nitrogen vacancies was synthesized using a molecular selfassembly *** s dopants and N vacancies synergistically adjusted the band structure,facilitating light absorption and enhancing the oxidation ***,the ultrathin nanosheets and porous structure provided more exposed active sites and facilitated mass and charge ***,s-c_(3)N_(4−y) foam exhibited enhanced photocatalytic activities for synchronous hydrogen evolution(4960μmol/(h·g))and benzylamine oxidation to N-benzylidenebenzylamine(4885μmol/(h·g))with high selectivity of>99%,which were approximately 17.6 and 72.9 times higher than those of bulk cN,*** photocatalytic coupling pairing reaction promotes the water splitting by consuming H2O2,thereby improving the hydrogen evolution efficiency and achieving the production of high value-added *** study provides an effective route for regulating the morphology and band structure of carbon nitride for synthesizing highly valuable chemicals.

关键词： photocatalysis s-doped carbon nitride band structure regulation hydrogen evolution coupled with benzylamine oxidation reaction mechanism

A Li_(3)P nanoparticle dispersion strengthened ultrathin Li metal electrode for high energy density rechargeable batteries

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Nano Research 2024年第5期17卷 4031-4038页

作者： Lin fu Xiancheng Wang Bao Zhang Zihe chen Yuanjian Li Yongming sun Provincial Guizhou Key Laboratory of Green chemical and clean Energy Technology School of Chemistry and Chemical EngineeringGuizhou UniversityGuiyang 550025China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China school of Physical and Mathematical sciences Nanyang Technological UniversitySingapore 637371Singapore Institute of Materials Research and Engineering Agency for Science Technology and Research(A*STAR)Singapore 138634Singapore

Achievement of lithium(Li)metal anode with thin thickness(e.g.,≤30µm)is highly desirable for rechargeable high energy density ***,the fabrication and application of such thin Li metal foil electrode remain challenging due to the poor mechanical processibility and inferior electrochemical performance of metallic ***,mechanico-chemical synthesis of robust ultrathin Li/Li_(3)P(LLP)composite foils(~15µm)is demonstrated by employing repeated mechanical rolling/stacking operations using red P and metallic Li as raw *** in-situ formed Li+-conductive Li_(3)P nanoparticles in metallic Li matrix and their tight bonding strengthen the mechanical durability and enable the successful fabrication of free-standing ultrathin Li metal composite ***,it also reduces the electrochemical Li nucleation barrier and homogenizes Li plating/stripping *** matching to high-voltage LicoO_(2),the full cell with a low negative/positive(N/P)capacity ratio of~1.5 offers a high energy density of~522 W·h·kg^(-1) at 0.5 c based on the mass of cathode and *** into account its facile manufacturing,potentially low cost,and good electrochemical performance,we believe that such an ultrathin composite Li metal foil design with nanoparticle-dispersion-strengthened mechanism may boost the development of high energy density Li metal batteries.

关键词： lithium metal anode high energy density battery mechanico-chemical synthesis ultrathin Li/Li_(3)P composite foil low negative/positive capacity ratio

How interfacial electron-donating defects influence the structure and charge of gold nanoparticles on TiO_(2)support

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Nano Research 2024年第7期17卷 5965-5974页

作者： Guang-Jie Xia Yu fu Wei cao Jun Li Yang-Gang Wang Department of chemistry and Guangdong Provincial Key Laboratory of catalysis Southern University of Science and TechnologyShenzhen 518055China school of Physical sciences Great Bay UniversityDongguan 523000China Department of chemistry Tsinghua UniversityBeijing 100084China

The reduction degree of TiO_(2)support is critical to the performances of metal *** many previous theoretical calculations,only the bridge oxygen vacancy(Ov)was considered as the electron-donating defect on reduced rutile TiO_(2)(r-TiO_(2−x))***,titanium adatoms(Tiad.),oxidized titanium islands(***),and acid hydroxyls(ObrH)also exist at the metal/support *** conducting density functional theory(DFT)calculations and ab initio molecular dynamics(AIMD)simulations,we compared r-TiO_(2−x)surfaces with Ov,Tiad.,***,and ObrH sites loaded with Au nanoparticles(NPs).The results showed the Au NPs were oxygen-phobic but titanium-philic,resulting in wetting of Ov and *** short contact with *** and *** Bader charges of Au NPs(QM)showed a good linear relationship with the ideal number of donating electrons(Ne)from the defective sites(QM=−KeNe+QM,s),demonstrating the intrinsic electron allocation at the *** Ov,Tiad.,and *** exhibited similar slopes(Ke),relatively steeper than that of *** means in the scope of Au NP charge state,the *** *** have a close electron-donating ability with Ov,but the ObrH donates relatively fewer *** linear relationship can be extended approximately to other *** higher the metal work function,the steeper the Ke for easier electron donation from defective *** stronger the metal oxygen affinity,the more positive the intercept(QM,s).That explains the easy generation of metallic or negative Pt and Au NPs on r-TiO_(2−x),but hard for cu and Zn in *** provides theoretical guidance for regulating the charge of metal NPs over TiO_(2−x)supports.

关键词： metal-support interaction titanium oxide oxygen vacancy surface hydroxyl titanium adatom

An integrated strategy of UPLc-Q-TOF/Ms and HPTLc/PAD-DEsI-MsI for the analysis of chemical variations:A case study of Tibetan medicine Tiebangchui

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Journal of Pharmaceutical Analysis 2024年第4期14卷 615-618页

作者： Yue Liu Mengjia Li Xing fu Yi Zhang ce Tang state Key Laboratory of southwestern chinese Medicine Resources School of Ethnic MedicineChengdu University of Traditional Chinese MedicineChengdu611137China Meishan Hospital of chengdu University of Traditional chinese Medicine MeishanSichuan620010China Innovative Institute of chinese Medicine and Pharmacy Chengdu University of Traditional Chinese MedicineChengdu611137China

The dried roots of Aconitum pendulum Busch are the major source of a commonly used Tibetan medicine,namely Tiebangchui(TBc)(Fig.s1).However,raw TBc contains a large amount of high toxic diester-diterpenoid alkaloids(DDAs),and the improper use would cause arrhythmia,irreversible cardiovascular damages,and even death.“Paozhi”,an appropriate processing method,is the essential prerequisite for the safe clinical application of ***-decocting and sand-frying are commonly used processing methods for toxicity attenuation and efficacy preservation for TBc.

关键词： dried irreversible roots

A grapefruit microstructure fiber temperature sensor coated with liquid crystal based on waist-enlarged taper

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Optoelectronics Letters 2024年第3期20卷 142-146页

作者： WANG Feng LI Jiaxuan ZHANG Rongjing fu Xinghu college of Mechanical and Electrical Engineering Hebei Normal University of Science&TechnologyQinhuangdao 066004China school of Information science and Engineering Key Laboratory for Special Fiber and Fiber Sensor of Hebei ProvinceYanshan UniversityQinhuangdao 066004China

In this paper, a grapefruit microstructure fiber(GMF) temperature sensor coated with liquid crystal(Lc) based on waist-enlarged taper is proposed and fabricated, and its temperature sensing characteristics are analyzed. The waist-enlarged taper is formed at the fusion point between single mode fiber(sMF) and GMF. The capillary glass tube is sleeved outside GMF, Lc is filled into the capillary glass tube, and its two ends are finally sealed to form a sensor. The experimental results show that when the length of GMF is 2.5 cm, the temperature sensitivity of the sensor can reach up to 195.3 pm/℃ in the range of 30-90℃, and it has a good stability for reuse. Thereby, it can be used in biochemical, industrial production and other temperature detection areas.

关键词： capillary fiber microstructure

The Effect of Blending Ratio on the structure and Properties of the PPR/Ps In situ Fiber Reinforced system Prepared by Multi-Flow Vibration Injection Molding

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chinese Journal of Polymer science 2024年第6期42卷 851-863页

作者： Yan-Jiang Li Meng-Long Hu Jun-Wen Zhang Qiang fu Jie Zhang college of Polymer science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065China

To enhance the mechanical properties of polypropylene random copolymer(PPR),polystyrene(Ps)with four different contents were added to the PPR matrix through melt ***,using the Multi-Flow Vibration Injection Molding(MFVIM)technology,PPR/Ps in situ microfiber composites(MFc)with different blending ratios were *** results indicated that blending ratio had a great impact on the phase morphology and crystal structure of MFVIM samples,which was different from those of conventional injection molding(cIM)*** ultrafine fibers could be formed under the shear field and could absorb the PPR molecular chains to form hybrid shish-kebab ***,the PPR matrix could also form shish-kebab structures under the effect of strong *** the Ps content reached 20%,under the combined action of Ps in situ microfibers and highly oriented crystal structure,the tensile strength and Young’s modulus of the sample were obviously improved and the impact strength remained at a relatively high *** a strong and tough balanced PPR based material was *** results provide valuable insights for expanding the industrial and daily-life applications of PPR and show promising development prospects.

关键词： PPR MFVIM In situ microfibers shearfield Hybrid shish-kebab structures