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The noise spectral cha.acteristics and noise reduction schemes of screw air-source heat pump:A case study

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Building Simulation 2024年第1期17卷 53-70页

作者： Dongsheng Liu ya.han Feng Jikang jia Pengfei Si ya.Feng China Southwest Architecture Design and Research Institute Co.Ltd. Chengdu 610041China CSCEC green Construction Engineering Research Center Chengdu 610041China

The screw air-source heat pump can cause incessant high noise levels during operation,which might hinder adoption of this energy-efficient heat ***,acoustic measurements and comparison testing were performed in this *** measurements revealed that the compressor is the main noise source of the heat pump,and it shows a multipeak frequency distribution and a wide frequency spectrum under different work conditions,with multiple peaks at 63,250,and 1000 ***,a compressor sound insulation cover with broadband absorption was proposed,and it was experimentally proven that the insulation cover can reduce the maximum sound pressure level of one unit from 89.8 dBA to 79.1 ***,we proposed several noise reduction strategies and compared their noise reduction effects using computer *** results showed that the noise problem can be effectively improved through the rational design of the sound barrier and the layout and opening options of heat *** distance between the sound barrier and heat pump and the sound attenuation due to diffraction ALa exhibit a U-shaped *** buildings of different heights,the optimal heights of noise barrier are *** 5.5-meter is the optimal height of the sound barrier for single-story *** conclusions can be applied to other building projects for heat pump noise reduction.

关键词： acoustic simulation broadband noise noise reduction air-source heat pump sound barrier

Anti-corrosive and highly reversible zinc metal anode enabled by the phenolic resin coating

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Rare Metals 2024年第5期43卷 2115-2124页

作者： ya.Ping Wang ya.Di ya.g Shu-Qi Duan Li Wang jia-Shuo guo An-Qiang Pan School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China Key Laboratory of Special Functional Materials for Ecological Environment and Information(Hebei University of Technology).Ministry of Education Tianjin 300130China Key Laboratory for New Type of Functional Materials in Hebei Province Hebei University of TechnologyTianjin 300130China School of Materials Science and Engineering Central South UniversityChangsha 410083China

Aqueous zinc-ion batteries have attracted much attention due to their high theoretical capacity,low cost high safety,and ***,cha.lenges such as dendrite growth and side reactions severely hinder the electrochemical performance of the Zn anode,leading to low Coulombic efficiency(CE)or even short circuits Herein,phenolic resin(PF)is used as a protective coating on the surface of the zinc metal *** PF layer can greatly improve the corrosion resistance of the Zn electrode in the ***,this artificial electrode/electrolyte interphase also elevates the nucleation barrier and restrains Zn^(2+)2D diffusion,regulating the zinc deposition/dissolution *** a result,PF@Zn symmetric cells exhibit superior performance than that of bare Zn symmetric cells,achieving a stable and dendrite-free cycle of 1400 ***,the carbon nanotube MnO_(2)||PF@Zn(CNT/MnO_(2)||PF@Zn)full cell also delivers a long cycle life with a high-capacity retention of about 180.0 m Ah·g^(-1)after 1400 cycles,far exceeding that of bare Zn *** work provides a facile strategy for achieving a dendrite-free and recha.geable zinc anode.

关键词： Recha.geable aqueous batteries Zn metal anode Phenolic resin Anti-corrosion

Influence of pressure disturbance wave on dynamic response cha.acteristics of liquid film seal for multiphase pump

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Petroleum Science 2024年第3期21卷 2048-2065页

作者： Qing-Ping Li Jin-ya.Zhang jia-Xiang Zhang Yong-Xue Zhang CNOOC Research Institute Company Limited Beijing100028China State Key Laboratory of Natural gas Hydrate Beijing100028China College of Mecha.ical and Transportation Engineering China University of PetroleumBeijing2249China

Slug flow or high gVF(gas Volume Fraction)conditions can cause pressure disturbance waves and alternating loads at the boundary of mecha.ical seals for multiphase pumps,endangering the safety of multiphase pump *** mecha.ical seal model is simplified by using periodic boundary conditions and numerical calculations are carried out based on the Zwart-gerber-Belamri cavitation ***(User Define Function)programs such as structural dynamics equations,alternating load equations,and pressure disturbance equations are embedded in numerical calculations,and the dynamic response cha.acteristics of mecha.ical seal are studied using layered dynamic mesh *** results show that when the pressure disturbance occurs at the inlet,as the amplitude and period of the disturbance increase,the film thickness gradually *** the fundamental reason for the hysteresis of the film thickness cha.ge is that the pressure in the high-pressure area cannot be restored in a timely *** maximum value of leakage and the minimum value of axial velocity are independent of the disturbance period and determined by the disturbance *** mutual interference between enhanced waves does not have a significant impact on the film thickness,while the front wave in the attenuated wave has a promoting effect on the subsequent film thickness cha.ges,and the fluctuation of the liquid film cavitation rate and axial velocity under the attenuated wave condition deviates from the initial *** with pressure disturbance conditions,alternating load conditions have a more significant impact on film thickness and *** actual operation,it is necessary to avoid alternating load conditions in multiphase pump mecha.ical seals.

关键词： Multiphase pump Liquid film seal Pressure disturbance wave Dynamic response cha.acteristics

From ancient wisdom to modern science:gut microbiota sheds light on property theory of traditional Chinese medicine

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Journal of Integrative Medicine 2024年第4期22卷 413-444页

作者： ya.nan ya.g jia.guo Zhan Ying Cao Chong-ming Wu School of Chinese Materia Medica Tianjin University of Traditional Chinese MedicineTianjin 301617China Tianjin Key Laboratory of Therapeutic Substance of Traditional Chinese Medicine Tianjin 301617China

The property theory of traditional Chinese medicine(TCM) has been practiced for thousands of years,playing a pivotal role in the clinical application of TCM. While advancements in energy metabolism,chemical composition analysis, machine learning, ion current modeling, and supercritical fluid technology have provided valuable insight into how aspects of TCM property theory may be measured, these studies only capture specific aspects of TCM property theory in isolation, overlooking the holistic perspective inherent in TCM. To systematically investigate the modern interpretation of the TCM property theory from multidimensional perspectives, we consulted the Chinese Pharmacopoeia(2020 edition) to compile a list of Chinese materia medica(CMM). Then, using the Latin names of each CMM and gut microbiota as keywords, we searched the PubMed database for relevant research on gut microbiota and CMM. The regulatory patterns of different herbs on gut microbiota were then summarized from the perspectives of the four natures, the five flavors and the meridian tropism. In terms of the four natures, we found that warm-natured medicines promoted the colonization of specific beneficial bacteria,while cold-natured medicines boosted populations of some beneficial bacteria while suppressing pathogenic bacteria. Analysis of the five flavors revealed that sweet-flavored and bitter-flavored CMMs positively influenced beneficial bacteria while inhibiting harmful bacteria. CMMs with different meridian tropism exhibited complex modulative patterns on gut microbiota, with Jueyin(Liver) and Taiyin(Lung) meridian CMMs generally exerting a stronger effect. The gut microbiota may be a biological indicator for cha.acterizing the TCM property theory, which not only enhances our understanding of classic TCM theory but also contributes to its scientific advancement and application in healthcare.

关键词： Traditional Chinese medicine Property theory gut microbiota Four natures Five flavors Meridian tropism

Acupuncture for obesity and related diseases:Insight for regulating neural circuit

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Journal of Integrative Medicine 2024年第2期22卷 93-101页

作者： Lin-ya. jia.g Jun Tian ya.nan ya.g Shao-hui jia Qing Shu Department of Rehabilitation Medicine Zhongnan HospitalWuhan UniversityWuhan 430071Hubei ProvinceChina School of Sports Medicine Wuhan Sports UniversityWuhan 430079Hubei ProvinceChina Department of Traditional Chinese Medicine China Resources&Wu Gang General HospitalWuhan 430080Hubei ProvinceChina

Obesity is defined as abnormal or excessive fat accumulation that may impair *** is associated with numerous pathological cha.ges including insulin resistance,fatty liver,hyperlipidemias,and other obesity-related *** comorbidities comprise a significant public health *** anti-obesity drugs have been limited by side effects that include depression,suicidal thoughts,cardiovascular complications and *** treatment has been shown to be effective for treating obesity and obesity-related conditions,while avoiding side ***,the mecha.isms of acupuncture in treating obesity-related diseases,especially its effect on neural circuits,are not well understood.A growing body of research has studied acupuncture’s effects on the endocrine system and other mecha.isms related to the regulation of neural *** this article,recent research that was relevant to the use of acupuncture to treat obesity and obesity-related diseases through the neuroendocrine system,as well as some neural circuits involved,was *** on this,acupuncture’s potential ability to regulate neural circuits and its mecha.isms of action in the endocrine system were reviewed,leading to a deeper mecha.istic understanding of acupuncture’s effects and providing insight and direction for future research about obesity.

关键词： Obesity Acupuncture Neural circuit Appetite Energy metabolism

Experimental investigation on pyrolysis products and pore structure cha.acteristics of organic-rich shale heated by supercritical carbon dioxide

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Petroleum Science 2024年第4期21卷 2393-2406页

作者： Bai-Shuo Liu Chuan-Jin ya. jia-Long Qi ya.Qian Liu Liang Xu Jing-Xuan Hou State Key Laboratory of Deep Oil and gas China University of Petroleum (East China) Key Laboratory of Unconventional Oil & gas Development (China University of Petroleum (East China)) Ministry of Education School of Petroleum Engineering China University of Petroleum (East China)

The efficient pyrolysis and conversion of organic matter in organic-rich shale,as well as the effective recovery of pyrolysis shale oil and gas,play a vital role in alleviating energy *** state of carbon dioxide（CO2） in the pyrolysis environment of shale reservoirs is the supercritical *** unique supercritical fluid properties not only effectively heat organic matter,displace pyrolysis products and cha.ge shale pore structure,but also achieve carbon storage to a certain *** samples were made into powder and three sizes of cores,and nitrogen（N2） and supercritical carbon dioxide（ScCO2）pyrolysis experiments were performed at different final pyrolysis *** properties and mineral cha.acteristics of the pyrolysis products were studied based on gas chromatography analysis,Xray diffraction tests,and mass spectrometry ***,the pore structure cha.acteristics at different regions of cores before and after pyrolysis were analyzed using N2adsorption tests to clarify the impact of fracturing degree on the pyrolysis *** results indicate that the optimal pyrolysis temperature of Longkou shale is about 430℃.Compared with N2,the oil yield of ScCO2pyrolysis is *** pyrolysis oil obtained by ScCO2extraction has more intermediate fractions and higher relative molecular *** ScCO2can effectively improve the pore diameter of shale and its effect is better than that of *** micropores are produced in shale after pyrolysis,and the macropores only are generated in ScCO2pyrolysis environments with temperatures greater than 430℃.The pore structure has different development cha.acteristics at different pyrolysis temperatures,which are mainly affected by the pressure holding of volatile matter and products *** to the surface of the core,the pore development effect inside the core is *** the decrease in core size,the pore diameter,specific surface area,and pore volume of cores all increase after pyrolysis.

关键词： Organic-rich shale Supercritical carbon dioxide In-situ pyrolysis Pore structure Core size and region

Mecha.ism of high-energy pulsed current-assisted rolling of 08AL carbon steel ultra-thin strip

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Journal of Iron and Steel Research International 2024年第2期31卷 416-427页

作者： Zhong-kai Ren ya.nan Xu jia-zhao Chen He Li Rui-lin Yuan Zhen-hua Wang Tao Wang Xiao Liu College of Mecha.ical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment(Ministry of Education) Taiyuan University of TechnologyTaiyuan030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment China National Heavy Machinery Research Institute Co.Ltd.Xi’an710016ShaanxiChina

To improve the plastic deformation performance of a 08AL carbon steel ultra-thin strip,a pulsed electric field was integrated into the plastic processing of the ultra-thin strip,and the effects of high-energy current on its deformation ability were ***-assisted tensile tests were employed,and the results clarified that the pulsed current could reduce the activation energy of faults and promoted dislocation slip within grains and at grain boundaries,leading to a decrease in the deformation resistance of the metal and an increase in its plastic *** the current density of 2.0 A/mm2,the yield strength,tensile strength,and elongation of the rolled sample reached 425 MPa,467 MPa,and 12.5%,*** the rolling process,it was found that the pulsed current promoted the dynamic recrystallization of the ultra-thin strip,reduced its dislocation density and deformation resistance,and promoted the coordinated deformation of the metal.

关键词： 08AL ultra-thin strip High-energy pulsed current Mecha.ical property Dislocation density Dynamic recrystallization

cha.acteristics of life-cycle carbon dioxide emissions of arterial highway maintenance and the influencing factors

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Advances in Climate cha.ge Research 2024年第4期15卷 751-765页

作者： ya. WANg Yuan-Qing WANg Shu-Juan JI Si-jia SUN Shu-Hong MA ya.Nan gAO Key Laboratory of Transport Industry of Management Control and Cycle Repair Technology for Traffic Network Facilities in Ecological Security Barrier Area Chang'an UniversityXi'an 710064China guangzhou Aids to Navigation Office Southem Navigation Service CenterMaritime Safety AdministrationGuangzhou 51000China

With the focus of highway development transitioning from construction to maintenance,a comprehensive understanding of the cha.acteristics and influencing factors of carbon dioxide(CO_(2))emissions from highway maintenance activities is crucial for formulating effective strategies to promote the low-carbon development of road ***,the quantitative relationships between CO_(2) emissions from highway maintenance schemes and factors such as pavement deterioration,traffic volume,and road grade remain unclear owing to a lack of compre-hensive,multi-category,and real *** real maintenance data from 340 arterial highway segments in China,this study conducts the life cycle assessment(LCA)to estimate CO_(2) emissions from maintenance activities and examines the primary emission sources among various structural layers and ***,multiple linear regression(MLR)analysis is conducted to investigate the impact of traffic volume,road grade,and pavement deterioration on CO_(2) emissions from maintenance projects,and factors influencing the early-stage degradation of pavement *** results demonstrate that average CO_(2) emissions from heavy rehabilitation projects are 6.97 times higher than those from medium rehabilitation *** from heavy rehabilitation projects exhibit a significantly negative linear relationship with the riding quality index(RQI)before maintenance(pgnificant negative linear relationship with the pavement condition index(PCI)before maintenance(pgnificantly positively correlated with heavy vehicle traffic volume before maintenance(pge degradation of PCI after heavy rehabilitation and RQI after medium rehabilitation exhibit significantly negative linear relationships with their respective in-dicators before maintenance(pge d

关键词： Life cycle assessment(LCA) Arterial highway Maintenance Emission factor Pavement performance Traffic volume

Clinical usefulness of the baby vision test in young children and its correlation with the Snellen cha.t

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 348-352页

作者： ya.Lan Wang jia-Jun Wang Xi-Cong Lou Han Zou Yun-E Zhao The Eye Hospital of Wenzhou Medical University Hangzhou 310000Zhejiang ProvinceChina National Clinical Research Center for Ocular Diseases Wenzhou 325027Zhejiang ProvinceChina

AIM:To investigate the efficacy of a new visual acuity(VA)screening method,the baby vision test for young ***:A total 105 eyes of 65 children aged 2-8y were included in the *** testing was conducted using a standardized recognition acuity cha.t(Snellen visual cha.t:at 3 m)and the baby vision model *** baby vision device includes a screen,a near infrared camera and a *** were seated at a measured distance of 33-40 cm from a display for *** was estimated according to the highest resolution the children could *** VA data were converted to logarithm of the minimum angle of resolution(logMAR)for statistical *** VA results for each child were recorded and analyzed for ***:The mean VA measured using the Snellen visual cha.t was 0.62±0.32,and that assessed using the baby vision test was 0.66±*** 95%limit of agreement was-0.609 to 0.695,with 95.2%(100/105)plots within the 95%limits of *** values of the baby vision test were significantly correlated with those of the Snellen cha.t(R=0.274,P=0.005).CONCLUSION:The baby vision test can be used as a relatively reliable method for estimating VA in young *** new acuity assessment might be a valid predictor of optotype-measured acuity later in preverbal children.

关键词： baby vision test acuity assessment fix-and-follow system Snellen cha.t