Swirl-Loop Scavenging(SLS) improves the performance of 2-stroke aircraft diesel engine because the involved swirl may not only benefit the scavenging process, but also facilitate the fuel atomization and combustion. T...Swirl-Loop Scavenging(SLS) improves the performance of 2-stroke aircraft diesel engine because the involved swirl may not only benefit the scavenging process, but also facilitate the fuel atomization and combustion. The arrangement of scavenge port angles greatly influences incylinder flow distribution and swirl intensity, as well as the performance of the SLS engine. However, the mechanism of the effect and visualization experiment are rarely mentioned in the literature. To further investigate the SLS, Particle Image Velocimetry(PIV) experiment and Computational Fluid Dynamics(CFD) simulation are adopted to obtain its swirl distribution characteristics, and the effect of port angles on scavenging performance is discussed based on engine fired cycle simulation. The results illustrate that Reynolds Stress Turbulence model is accurate enough for in-cylinder flow simulation. Tangential and axial velocity distribution of the flow, as well as the scavenging performance, are mainly determined by geometric scavenge port angles ageom and βgeom . For reinforcement of scavenging on cross-sections and meridian planes, ageomvalue of27° and βgeom value of 60° are preferred, under which the scavenging efficiency reaches as high as 73.7%. Excessive swirl intensity has a negative effect on SLS performance, which should be controlled to a proper extent.展开更多
The glancing angle deposition( GLAD) method is a kind of physical vapor deposition and many kinds of self-standing nanostructured materials can be prepared. Here we report GLAD method to form selfstanding TiO_2 nanost...The glancing angle deposition( GLAD) method is a kind of physical vapor deposition and many kinds of self-standing nanostructured materials can be prepared. Here we report GLAD method to form selfstanding TiO_2 nanostructures on specific substrates,which makes photocatalysts easier to recycle. And smart designs of doping,decorating band gap matched materials can also make traditional photocatalysts take use of more visible light. In this review,we present some previous work fabricating nanostructured TiO_2 composites for enhanced photocatalytic performance by these methods.展开更多
AIM:To find out the association of secreted protein acidic and rich in cysteine(SPARC)-related modular calcium binding 2(SMOC2)gene variants rs2255680 and rs13208776 with genotypic and phenotypic characteristics in bo...AIM:To find out the association of secreted protein acidic and rich in cysteine(SPARC)-related modular calcium binding 2(SMOC2)gene variants rs2255680 and rs13208776 with genotypic and phenotypic characteristics in both familial and non-familial primary open angle glaucoma(POAG)patients.METHODS:A total of 212 POAG patients,comprising 124 familial and 88 non-familial,were enrolled.For genotyping the SMOC2 variant rs2255680,amplification refractory mutation system(ARMS)-polymerase chain reaction(PCR)method and PCR-restriction fragment length polymorphism(PCR-RFLP)were utilized for analyzing rs13208776 variant.RESULTS:The mean age of familial POAG patients was 50.92±9.12y,with 78 males and 46 females.The mean age of non-familial POAG patients was 53.14±13.44y,with 52 males and 36 females.The SMOC2 gene variant rs13208776 showed the significant association with POAG between familial and non-familial groups.The homozygous G/G variant was frequent among non-familial(60.2%)whereas the heterozygous G/A variant was more frequent in familial POAG patients(46%).There were significant differences in G/A variant between familial and non-familial glaucoma patients,and the risk was decreased to 0.53-fold in non-familial glaucoma patients[odds ratio(OR):0.53;95%confidence interval(CI):0.29-0.94;P=0.033]in codominant model.The risk was further reduced to 0.49-fold(95%CI:0.28-0.86;P=0.012)in dominant model for non-familial patients.No significant association of SMOC2 gene variant rs2255680 between familial and non-familial glaucoma patients was found in our population.The haplotype analysis showed the decreased risk for TA[OR:0.48(95%CI:0.29-0.79);P=0.004]and an increased risk for TG[OR=2.28(95%CI:1.22-4.25);P=0.01]haplotypes.CONCLUSION:Current findings show significant association of SMOC2 gene variant rs13208776 with POAG between familial and non-familial Pakistani patients.展开更多
Despite numerous research investigations to understand the influences of various structural parameters,to the authors'knowledge,no research has been the effect of different angles of incidence on stab response and...Despite numerous research investigations to understand the influences of various structural parameters,to the authors'knowledge,no research has been the effect of different angles of incidence on stab response and performance of different types of protective textiles.Three distinct structures of 3D woven textiles and 2D plain weave fabric made with similar high-performance fiber and areal density were designed and manufactured to be tested.Two samples,one composed of a single and the other of 4-panel layers,from each fabric type structure,were prepared,and tested against stabbing at[0○],[22.5○],and[45○]angle of incidence.A new stabbing experimental setup that entertained testing of the specimens at various angles of incidence was engineered and utilized.The stabbing bench is also equipped with magnetic sensors and a UK Home Office Scientific Development Branch(HOSDB)/P1/B sharpness engineered knives to measure the impact velocity and exerted impact energy respectively.A silicon compound was utilized to imprint the Back Face Signature(BFS)on the backing material after every specimen test.Each silicon print was then scanned,digitized,and precisely measured to evaluate the stab response and performance of the specimen based on different performance variables,including Depth of Trauma(DOT),Depth of Penetration(DOP),and Length of Penetration(LOP).Besides,the post-impact surface failure modes of the fabrics were also measured using Image software and analyzed at the microscale level.The results show stab angle of incidence greatly influences the stab response and performance of protective textiles.The outcome of the study could provide not only valuable insights into understanding the stab response and capabilities of protective textiles under different angle of incidence,but also provide valuable information for protective textile manufacturer,armor developer and stab testing and standardizing organizations to consider the angle of incidence while developing,testing,optimizing,and using protective textiles in various applications.展开更多
Two-dimensional(2D)moirématerials have attracted a lot of attention and opened a new research frontier of twistronics due to their novel physical properties.Although great progress has been achieved,the inability...Two-dimensional(2D)moirématerials have attracted a lot of attention and opened a new research frontier of twistronics due to their novel physical properties.Although great progress has been achieved,the inability to precisely and reproducibly manipulate the twist angle hinders the further development of twistronics.Here,we demonstrated an atomic force microscope(AFM)tip manipulation method to control the interlayer twist angle of epitaxial MoS_(2)/graphene heterostructure with an ultra-high accuracy better than 0.1°.Furthermore,conductive AFM and spectroscopic characterizations were conducted to show the effects of the twist angle on moirépattern wavelength,phonons and excitons.Our work provides a technique to precisely control the twist angle of 2D moirématerials,enabling the possibility to establish the phase diagrams of moiréphysics with twist angle.展开更多
In this paper, we propose a two-dimensional （2-D） angles of arrival （AOAs） estimation method based on a joint diagonalization of two spatio-temporal （ST） correlation matrices. The mathematical manipulations prop...In this paper, we propose a two-dimensional （2-D） angles of arrival （AOAs） estimation method based on a joint diagonalization of two spatio-temporal （ST） correlation matrices. The mathematical manipulations proposed in this paper take the structure of the array that enable estimating 2-D AOAs simultaneously without 2-D searching or pairing. The performance comparison shows that the proposed method is better than ST-DOA matrix method.展开更多
基金supported by the Basic Research Program of the National Natural Science Foundation of China (Nos. 51775025 and 51205015)China Key Research and Development Plan (No.2018YFB0104100)。
文摘Swirl-Loop Scavenging(SLS) improves the performance of 2-stroke aircraft diesel engine because the involved swirl may not only benefit the scavenging process, but also facilitate the fuel atomization and combustion. The arrangement of scavenge port angles greatly influences incylinder flow distribution and swirl intensity, as well as the performance of the SLS engine. However, the mechanism of the effect and visualization experiment are rarely mentioned in the literature. To further investigate the SLS, Particle Image Velocimetry(PIV) experiment and Computational Fluid Dynamics(CFD) simulation are adopted to obtain its swirl distribution characteristics, and the effect of port angles on scavenging performance is discussed based on engine fired cycle simulation. The results illustrate that Reynolds Stress Turbulence model is accurate enough for in-cylinder flow simulation. Tangential and axial velocity distribution of the flow, as well as the scavenging performance, are mainly determined by geometric scavenge port angles ageom and βgeom . For reinforcement of scavenging on cross-sections and meridian planes, ageomvalue of27° and βgeom value of 60° are preferred, under which the scavenging efficiency reaches as high as 73.7%. Excessive swirl intensity has a negative effect on SLS performance, which should be controlled to a proper extent.
基金Sponsored by the Ministry of Science and Technology of P.R.C(Grant No.2016YFE0104000)
文摘The glancing angle deposition( GLAD) method is a kind of physical vapor deposition and many kinds of self-standing nanostructured materials can be prepared. Here we report GLAD method to form selfstanding TiO_2 nanostructures on specific substrates,which makes photocatalysts easier to recycle. And smart designs of doping,decorating band gap matched materials can also make traditional photocatalysts take use of more visible light. In this review,we present some previous work fabricating nanostructured TiO_2 composites for enhanced photocatalytic performance by these methods.
基金Supported by Higher Education Commission of Pakistan(NRPU#2835)Pakistan Science Foundation Project No.Biotech 101,funded to Professor Dr.Ali Muhammad Waryah.
文摘AIM:To find out the association of secreted protein acidic and rich in cysteine(SPARC)-related modular calcium binding 2(SMOC2)gene variants rs2255680 and rs13208776 with genotypic and phenotypic characteristics in both familial and non-familial primary open angle glaucoma(POAG)patients.METHODS:A total of 212 POAG patients,comprising 124 familial and 88 non-familial,were enrolled.For genotyping the SMOC2 variant rs2255680,amplification refractory mutation system(ARMS)-polymerase chain reaction(PCR)method and PCR-restriction fragment length polymorphism(PCR-RFLP)were utilized for analyzing rs13208776 variant.RESULTS:The mean age of familial POAG patients was 50.92±9.12y,with 78 males and 46 females.The mean age of non-familial POAG patients was 53.14±13.44y,with 52 males and 36 females.The SMOC2 gene variant rs13208776 showed the significant association with POAG between familial and non-familial groups.The homozygous G/G variant was frequent among non-familial(60.2%)whereas the heterozygous G/A variant was more frequent in familial POAG patients(46%).There were significant differences in G/A variant between familial and non-familial glaucoma patients,and the risk was decreased to 0.53-fold in non-familial glaucoma patients[odds ratio(OR):0.53;95%confidence interval(CI):0.29-0.94;P=0.033]in codominant model.The risk was further reduced to 0.49-fold(95%CI:0.28-0.86;P=0.012)in dominant model for non-familial patients.No significant association of SMOC2 gene variant rs2255680 between familial and non-familial glaucoma patients was found in our population.The haplotype analysis showed the decreased risk for TA[OR:0.48(95%CI:0.29-0.79);P=0.004]and an increased risk for TG[OR=2.28(95%CI:1.22-4.25);P=0.01]haplotypes.CONCLUSION:Current findings show significant association of SMOC2 gene variant rs13208776 with POAG between familial and non-familial Pakistani patients.
文摘Despite numerous research investigations to understand the influences of various structural parameters,to the authors'knowledge,no research has been the effect of different angles of incidence on stab response and performance of different types of protective textiles.Three distinct structures of 3D woven textiles and 2D plain weave fabric made with similar high-performance fiber and areal density were designed and manufactured to be tested.Two samples,one composed of a single and the other of 4-panel layers,from each fabric type structure,were prepared,and tested against stabbing at[0○],[22.5○],and[45○]angle of incidence.A new stabbing experimental setup that entertained testing of the specimens at various angles of incidence was engineered and utilized.The stabbing bench is also equipped with magnetic sensors and a UK Home Office Scientific Development Branch(HOSDB)/P1/B sharpness engineered knives to measure the impact velocity and exerted impact energy respectively.A silicon compound was utilized to imprint the Back Face Signature(BFS)on the backing material after every specimen test.Each silicon print was then scanned,digitized,and precisely measured to evaluate the stab response and performance of the specimen based on different performance variables,including Depth of Trauma(DOT),Depth of Penetration(DOP),and Length of Penetration(LOP).Besides,the post-impact surface failure modes of the fabrics were also measured using Image software and analyzed at the microscale level.The results show stab angle of incidence greatly influences the stab response and performance of protective textiles.The outcome of the study could provide not only valuable insights into understanding the stab response and capabilities of protective textiles under different angle of incidence,but also provide valuable information for protective textile manufacturer,armor developer and stab testing and standardizing organizations to consider the angle of incidence while developing,testing,optimizing,and using protective textiles in various applications.
基金Project supported by the Natioanl Natural Science Foundation of China(Grant Nos.62122084,12074412,61888102,and 11834017)。
文摘Two-dimensional(2D)moirématerials have attracted a lot of attention and opened a new research frontier of twistronics due to their novel physical properties.Although great progress has been achieved,the inability to precisely and reproducibly manipulate the twist angle hinders the further development of twistronics.Here,we demonstrated an atomic force microscope(AFM)tip manipulation method to control the interlayer twist angle of epitaxial MoS_(2)/graphene heterostructure with an ultra-high accuracy better than 0.1°.Furthermore,conductive AFM and spectroscopic characterizations were conducted to show the effects of the twist angle on moirépattern wavelength,phonons and excitons.Our work provides a technique to precisely control the twist angle of 2D moirématerials,enabling the possibility to establish the phase diagrams of moiréphysics with twist angle.
基金This work was supported the National Natural Science Foundation of China under Grand No.60372022the Program for New Century Excellent Talents in University under Grand No. NCET-05-0806.
文摘In this paper, we propose a two-dimensional （2-D） angles of arrival （AOAs） estimation method based on a joint diagonalization of two spatio-temporal （ST） correlation matrices. The mathematical manipulations proposed in this paper take the structure of the array that enable estimating 2-D AOAs simultaneously without 2-D searching or pairing. The performance comparison shows that the proposed method is better than ST-DOA matrix method.
