Steel slag(SS)accumulates unavoidably due to its complex and unstable composition,high production volumes,and limited value-added resource utilization.Single or multiple interface modifiers were proposed to enhance th...Steel slag(SS)accumulates unavoidably due to its complex and unstable composition,high production volumes,and limited value-added resource utilization.Single or multiple interface modifiers were proposed to enhance the properties of SS through high-speed dispersion,transforming its inherent hydrophilic and oleophobic characteristics into hydrophily and lipophilicity.The modification effects were innovatively assessed by observing the color changes of modified steel slag solutions following the dissolution-settlement equilibrium constant.This approach avoided human-induced errors and improved estimated accuracy in conformance with conventional methods such as oil absorption value,activation index,sedimentation volume,and lipophilicity.The hydrolysis of 3-aminopropyltriethoxysilane(KH)generated–Si(OH)_(3)structure to form hydrogen or covalent bonds with active substances(OH groups)from SS.Concurrently,SS underwent encapsulation via Si–O–Si structure resulting from the dehydration of–Si(OH)_(3).The stearic acid coupling agent(SA),aluminate coupling agent(AC),and titanate coupling agent(TN)underwent chemical reactions with Ca(OH)_(2),Al(OH)_(3),and CaCO_(3)in SS.The acidic SA primarily created stable chemical bonds and acted as a supplement due to its package,reducing surface activity and hydrophilicity while enhancing lipophilicity.Specifically,the optimal modification effect was obtained at 3 wt.%SA.Consequently,3 wt.%SA was established as the benchmark for multiple modifiers and the most effective combination was 3 wt.%SA and 3 wt.%AC.Compared with a single interface modifier,SA corroded the SS surface to provide numerous active sites for further modification by KH,AC,or TN,resulting in a more densely packed structure.In addition,more organic groups on SS prevent the proximity of other particles from agglomerating to achieve dispersion and a synergistic modification,laying a theoretical foundation of SS in a new pathway for organic composite materials.展开更多
The excessive demand for phosphorus-based fertilizers is contributing to the undesired byproduct of phosphogypsum(PG),typically found in large quantities in phosphoric acid industry.Without proper management,this indu...The excessive demand for phosphorus-based fertilizers is contributing to the undesired byproduct of phosphogypsum(PG),typically found in large quantities in phosphoric acid industry.Without proper management,this industrial waste poses a significant environmental pollution risk.Current technologies are struggle to effectively handle the volume of PG produced,but one promising solution is its conversion into hemihydrate gypsum(CaSO_(4)·0.5 H_(2)O,HH).HH can exist in two phases,α-HH andβ-HH,withα-hemihydrate gypsum(α-HH)being preferred for its complete crystal structure and lower water requirement for hydration.The morphology ofα-HH gypsum is crucial for its material applications,and controlling crystal morphology is possible through the use of suitable crystal modifiers.This review explores various aspects of crystal modifiers and highlights their role in the preparation ofα-HH from PG.It suggests that leveraging the interfacial properties of PG could lead to innovative applications.Additionally,the review outlines future directions for PG development and identifies challenges to be addressed in the next steps.展开更多
The effect of combining different organic friction modifiers(OFMs)with ashless dispersants on the dispersion performance of lubricant oils in sludge was investigated using molecular dynamics(MD)simulations.polyisobuty...The effect of combining different organic friction modifiers(OFMs)with ashless dispersants on the dispersion performance of lubricant oils in sludge was investigated using molecular dynamics(MD)simulations.polyisobutylsuccinimide(PIBSI)was mixed with either glycerol monooleate(GMO)or oleamide(OAM)in a poly-α-olefin(PAO)base oil.The distribution and interaction energy of sludge precursors were analyzed both with and without these additive mixtures.The results show that both the OFMs and dispersants can form hydrogen bonds with sludge precursor molecules,preventing further aggregation.Adding OFMs to lubricant oil-containing dispersants enhances the dispersion of the lubricant.Compared to OAM,GMO forms more hydrogen bonds with sludge precursors,which favors improved dispersion.However,there is strong competition and interaction between GMO and PIBSI,which reduces the dispersant’s effectiveness in mitigating sludge precursor aggregation.The interactions among additives and their impact on performance should be considered when designing high-performance lubricant formulations.展开更多
Wood-polymer composites (WPC) were prepared from wood fiber and four kinds of plastics such as PE, PS, ABS, and SAN. The effects of different modifiers on the mechanical properties of the composites were studied. The ...Wood-polymer composites (WPC) were prepared from wood fiber and four kinds of plastics such as PE, PS, ABS, and SAN. The effects of different modifiers on the mechanical properties of the composites were studied. The results showed modifiers could raise the bonding strength of wood fiber with polymer and improve the mechanical properties of the composites. Different modifiers had different effects on the properties of wood-polymer composites, and comparatively the modifier of isocyanate produced a better result. Wood-polymer composite takes not only the advantages of both wood fiber and polymer, but waterproof, dimensional stability and dynamic strength are also significantly improved. Key word Wood fiber - Thermoplastic polyester - Wood-polymer composites - Modifier - Mechanical properties CLC number TB332 Document code A Foundation item: This study was supported by the Harbin Technology Tackle Key Plan (Development Research of Wood-Polymer Composites with High Wood Matrix) and by Heilongjing Nature Science Fund (Composite Mechanism Study of the Wood Polymer).Biography: XU Min (1963-), Female, Associate professor in Material Science and Engineering College, Northeast Forestry University, Harbin 150040, P. R. China.Responsible editor: Chai Ruihai展开更多
X-linked adrenoleukodystrophy(X-ALD),an inborn error of peroxisomalβ-oxidation,is caused by defects in the ATP Binding Cassette Subfamily D Member 1(ABCD1)gene.X-ALD patients may be asymptomatic or present with sever...X-linked adrenoleukodystrophy(X-ALD),an inborn error of peroxisomalβ-oxidation,is caused by defects in the ATP Binding Cassette Subfamily D Member 1(ABCD1)gene.X-ALD patients may be asymptomatic or present with several clinical phenotypes varying from severe to mild,severe cerebral adrenoleukodystrophy to mild adrenomyeloneuropathy(AMN).Although most female heterozygotes present with AMN-like symptoms after 60 years of age,occasional cases of females with the cerebral form have been reported.Phenotypic variability has been described within the same kindreds and even among monozygotic twins.There is no association between the nature of ABCD1 mutation and the clinical phenotypes,and the molecular basis of phenotypic variability in X-ALD is yet to be resolved.Various genetic,epigenetic,and environmental influences are speculated to modify the disease onset and severity.In this review,we summarize the observations made in various studies investigating the potential modifying factors regulating the clinical manifestation of X-ALD,which could help understand the pathogenesis of the disease and develop suitable therapeutic strategies.展开更多
The effects of plasticizers,antioxidants and burning rate modifiers on the aging performance of the composite solid propellant based on hydroxyl-terminated polybutadiene(HTPB)/hexamethylene diisocyanate(HMDI)were expl...The effects of plasticizers,antioxidants and burning rate modifiers on the aging performance of the composite solid propellant based on hydroxyl-terminated polybutadiene(HTPB)/hexamethylene diisocyanate(HMDI)were explored by apply-ing an accelerated aging program for 90 day at 70 ℃. The HTPB propellant matrix with the diisooctyl sebacate(DOS)as plasti-cizers and diisooctyl azelate(DOZ), antioxidants as N,N ′-Diphenyl-p-phenylenediamine(AO) and 2,2′-methylenebis(4-methyl-6-tert-butylphenol)(cyanox 2246)and burning rate modifiers as barium ferrite(BF),copper chromites(CC)and fer-ric oxide(FO)were varied. Results show that sample(S1)which based on DOS decreases the stress value and increases the strain value which considered to be an excellent start for aging program. Sample(S3)containing AO presents the higher resis-tance to oxidation showing the better performance that reflects on increasing the shelf life of the composite solid propellant mo-tor. Sample(S5)which based on BF enhances the ballistic performance among over the other tested two samples. The accelerat-ed aging program allowed us to estimate the motor in-service lifetime.展开更多
It is important to understand the mechanism and implications of different modifiers on analytical and preparative processes under chromatography with supercritical fluids (SFs) and under extraction with SFs. Supercrit...It is important to understand the mechanism and implications of different modifiers on analytical and preparative processes under chromatography with supercritical fluids (SFs) and under extraction with SFs. Supercritical fluid chromatography (SFC) and supercritical fluid extraction are generally carried out with neat supercritical carbon dioxide (SCCO2) or with SCCO2 containing modifiers (or cosolvents), especially for strongly polar compounds. For example, methanol is added as a cosolvent/modifier to SCCO2 for the extraction/separation of polar compounds. This paper discusses the influence of the modifier on the colligative properties of the principal mobile phase, which may define the situation in the total mobile phase in a chromatography column or in parts of a column under SFC. No colligative behavior of solutions reflects individual properties of the solutes. Their cross-interactions with solvents are discussed.展开更多
Modifiers have a broad array of influences on extraction with liquids in standard state, supercritical fluid extraction (SFE), trapping by SFE and supercritical fluid chromatography (SFC). They can significantly chang...Modifiers have a broad array of influences on extraction with liquids in standard state, supercritical fluid extraction (SFE), trapping by SFE and supercritical fluid chromatography (SFC). They can significantly change the qualitative and quantitative results. Quantitative and qualitative results can be influenced by different extractants and modifiers in different ways as it was shown by Brondz et al. at 2007 in “The real nature of the indole alkaloids in Cortinarius infractus: Evaluation of artifact formation through solvent extraction method development”, J. Chromatography A, 1148, 1-7. The choice of correct extractant, modifier, and trapper to the bulk mobile phase for supercritical fluids (SFs) or for liquids in subcritical or in the liquids in standard state is a challenge in any extraction procedure. This is the second paper in a sequence that describes the influence of extractants and modifiers on the performance of SFs and results of extraction with liquids in standard state and SFE. Here, attention is given to possible mistakes in qualitative and quantitative results by poor understanding of the influence of extractants, modifiers, and trappers on extraction and trapping process by a careless choice of extractant, modifier, and trapper for extraction with liquids in standard state and SFE. The SF chosen for discussion in the paper is CO2. However, similar effects can be observed with use of other SFs and fluids in subcritical and standard states. In this paper, the discussion of lipids, fatty and carboxylic acids have been chosen as target analytes for extraction, trapping and analysis. Some examples from extraction with liquids in the standard state and trapping in the supercritical state (collection) have been furnished with the wrong extractant, modifier, or trapper which is presented for illustration of inappropriate choice of extractants, modifiers, and trappers.展开更多
Various of modifiers were used to modify the surface activity of white carbon black. The oil absorption, viscosity, hydrophobic rate and burning loss of white carbon black and the mechanical propertiess of silicone ru...Various of modifiers were used to modify the surface activity of white carbon black. The oil absorption, viscosity, hydrophobic rate and burning loss of white carbon black and the mechanical propertiess of silicone rubber were measured. The influences of the modifiers on the properties of white carbon black and the mechanical properties of silicone rubber were discussed.展开更多
Using SrC12-6H2O and Na2CO3 as the main raw materials and adding different complexons as modifiers with simple co-precipitation method, SrCO3 crystals with distinct morphologies like spherical, bundle-like, overlappin...Using SrC12-6H2O and Na2CO3 as the main raw materials and adding different complexons as modifiers with simple co-precipitation method, SrCO3 crystals with distinct morphologies like spherical, bundle-like, overlapping plate-like, hexagonal star-like, dumbbell-like, etc. can be synthesized in the ethanol-water mixtures. The samples were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and Fourier transform infrared spectrograph （FT-IR）. The interrelated effect mechanism is presented in the end. Results show that the modifier carboxyl groups play a significant role in controlling the SrCO3 crystal morphologies, which can alter the crystal growth unit （Sr^2＋） supply mode and induce the crystal formation with the morphologies matching their spatial configurations.展开更多
The effects of modifiers on the anti-wetting and anti-icing property of the prepared rough aluminum surface were investigated.The rough aluminum substrates were obtained through electrochemical oxidization with 15 wt%...The effects of modifiers on the anti-wetting and anti-icing property of the prepared rough aluminum surface were investigated.The rough aluminum substrates were obtained through electrochemical oxidization with 15 wt% sulfuric acid solution as the electrolyte at the constant current of 4 mA for 3 h.And then they were modified with octadecanoic acid (C18),polyethylene (PE),polystyrene (PS),polyethylene glycol (PEG) and hexamethylenetetramine (HMTA),respectively,whose surface free energies were 27.6,31.0,33.0,61.6 and 70.0 mN/m,respectively.The contact angles (CA) were 154.6°,128.4°,127.6°,5.0° and 0.0°,respectively,and the ice adhesion pressures were 15.9,36.3,55.9,155.3 and 216.1 kPa,respectively.The ice adhesion strengths decrease along with the increasing anti-wetting property of aluminum surfaces and the decreasing of the surface energy of modifiers.These provide some new insights when designing the aluminum surface with anti-icing properties in some special applications.展开更多
In order to verify the influence of different block proportions S/B on the effect of SBS modified asphalt,the dynamic mechanical performance test and static loading test were performed on the samples composed of diffe...In order to verify the influence of different block proportions S/B on the effect of SBS modified asphalt,the dynamic mechanical performance test and static loading test were performed on the samples composed of different kinds of SBS with base asphalt. It is found that different S/B values fix on different modified effects and different viscoelastic mechanical behaviors,due to biphasic separate fabric of polybutadiene and polystyrene in SBS. In low-speed running pavement,the modified asphalt with lower S/B value shows better pavement performance,while in high-speed running pavement,the modified asphalt with higher S/B value shows better pavement performance. As far as SBS modified asphalt itself is concerned,mixing proportion impacts on resisting displacement and block proportion S/B ratio impacts on strain recovery capacity. In the case that the conditions are the same,SBS modified asphalt with different S/B values can be used for different travelling speed pavement construction demands to get an intelligent use.展开更多
By modifying friction to the desired level,the application of friction modifiers(FMs)has been considered as a promising emerging tool in the railway engineering for increasing braking/traction force in poor adhesion c...By modifying friction to the desired level,the application of friction modifiers(FMs)has been considered as a promising emerging tool in the railway engineering for increasing braking/traction force in poor adhesion conditions and mitigating wheel/rail interface deterioration,energy consumption,vibration and noise.Understanding the effectiveness of FMs in wheel–rail dynamic interactions is crucial to their proper applications in practice,which has,however,not been well explained.This study experimentally investigates the effects of two types of top-of-rail FM,i.e.FM-A and FM-B,and their application dosages on wheel–rail dynamic interactions with a range of angles of attack(AoAs)using an innovative well-controlled V-track test rig.The tested FMs have been used to provide intermediate friction for wear and noise reduction.The effectiveness of the FMs is assessed in terms of the wheel–rail adhesion characteristics and friction rolling induced axle box acceleration(ABA).This study provides the following new insights into the study of FM:the applications of the tested FMs can both reduce the wheel–rail adhesion level and change the negative friction characteristic to positive;stick–slip can be generated in the V-Track and eliminated by FM-A but intensified by FM-B,depending on the dosage of the FMs applied;the negative friction characteristic is not a must for stick–slip;the increase in ABA with AoA is insignificant until stick–slip occurs and the ABA can thus be influenced by the applications of FM.展开更多
Reflector edges, sharp acceptance angles and by-pass diodes introduce large variations in the electrical performance of asymmetrical concentrating photovoltaic/thermal modules over a short incidence angle interval. It...Reflector edges, sharp acceptance angles and by-pass diodes introduce large variations in the electrical performance of asymmetrical concentrating photovoltaic/thermal modules over a short incidence angle interval. It is therefore important to quantify these impacts precisely. The impact on the electrical performance of the optical properties of an asymmetrical photovoltaic/thermal CPC-collector was measured in Maputo, Mozambique. The measurements were carried out with the focus on attaining a high resolution incidence angle modifier in both the longitudinal and transversal directions, since large variations were expected over small angle intervals. A detailed analysis of the contribution of the diffuse radiation to the total output was also carried out. The solar cells have an electrical efficiency of 18% while the maximum measured electrical efficiency of the collector was 13.9 % per active glazed area and 20.9 % per active cell area, at 25 °C. Such data make it possible to quantify not only the electrical performance for different climatic and operating conditions but also to determine potential improvements to the collector design. The electrical output can be increased by a number of different measures, e.g. removing the outermost cells, turning the edge cells 90°, dividing each receiver side into three or four parts and directing the tracking, when used, along a north-south axis.展开更多
Poly (vinyl chloride)/ethylene-vinyl acetate/montmorillonite (PVC/EVA/OMMT) composites were prepared by melt blending method. Two kinds of montmorillonites were organically modified by trimethyloctadecyl ammonium and ...Poly (vinyl chloride)/ethylene-vinyl acetate/montmorillonite (PVC/EVA/OMMT) composites were prepared by melt blending method. Two kinds of montmorillonites were organically modified by trimethyloctadecyl ammonium and dimethyl bis (hydrogenated tallow) ammonium, respectively. The morphology and tensile properties of the resultant composites were discussed in terms of the modifier type and OMMT content. The PVC/EVA/OMMT composites have intercalated structure, which is independent of the polarity of the modifiers, while the tensile properties show strong dependence on the modifier type. The OMMT modified by polar modifier gives higher tensile ductile and strength of PVC/EVA/OMMT composites.展开更多
The integrated absorption cross section Σ abs, peak emis sion cross section σ emi, Judd-Ofeld intensity parameters Ω t(t=2,4,6), and spontaneous emission probability A R of Er 3+ ions were determined fo r...The integrated absorption cross section Σ abs, peak emis sion cross section σ emi, Judd-Ofeld intensity parameters Ω t(t=2,4,6), and spontaneous emission probability A R of Er 3+ ions were determined fo r Erbium doped alkali and alkaline earth phosphate glasses. It is found the comp ositional dependence of σ emi is almost similar to that of Σ abs, wh ich is determined by the sum of Ω t (3Ω 2+10Ω 4+21Ω 6). In addition, the compositional dependence of Ω t was studied in these glass systems. As a resu lt, compared with Ω 4 and Ω 6, the Ω 2 has a stronger compositional depend ence on the ionic radius and content of modifiers. The covalency of Er-O bonds in phosphate glass is weaker than that in silicate glass, germanate glass, alumi nate glass, and tellurate glass, since Ω 6 of phosphate glass is relatively la rge. A R is affected by the covalency of the Er 3+ ion sites and correspon ds to the Ω 6 value.展开更多
The modification effect of CX-type (CX means the modifiers that have longeffective term) modifiers applied in ZL108 and ZL104 Al-Si alloys has been studied in detail. Theresults show that the morphologies of the eutec...The modification effect of CX-type (CX means the modifiers that have longeffective term) modifiers applied in ZL108 and ZL104 Al-Si alloys has been studied in detail. Theresults show that the morphologies of the eutectic silicon and the primary silicon can be modifiedand refined simultaneously. The modification effect acts quickly and can maintain a period of 8 h bythe CX-type modifiers. The CX-type modifiers increase the mechanical properties of Al-Si alloys andimprove the service properties of machine parts made of Al-Si alloys (such as piston and cylinderetc.). In modifying processes, the amount of the addition of CX-type modifiers is smaller than thatof any other modifiers, and the modifying procedures are simple. There are no smoke, no dust, and noirritant smell in modifying processes using CX-type modifiers. Therefore, the CX-type modifiershave advantages in economy and environment protection.展开更多
There are both premodifiers and postmodifiers English noun phrases.Premodifiers and postmodifiers can be change able along with the adjustments of human cognition.It discusses the cognitive foundation of transformatio...There are both premodifiers and postmodifiers English noun phrases.Premodifiers and postmodifiers can be change able along with the adjustments of human cognition.It discusses the cognitive foundation of transformation between postmodifi ers and premodifiers in English noun phrases so as to find out the cognitive reason behind linguistic structure.展开更多
This research aims to investigate the correlation between translators’construal of implicit modifiers in Chinese political chunks and their performance in target English translation.Five major types of the explicitat...This research aims to investigate the correlation between translators’construal of implicit modifiers in Chinese political chunks and their performance in target English translation.Five major types of the explicitation of Chinese implicit modifiers in English translation have been found,namely,zero,varied,partial,identical,and mixed ones.In addition,significant differences were found between student and expert translators in construing and manifesting the implicit modifiers in Chinese ST.These findings shed light on bilingualeducation in Chinese universities and the importance of raising awareness of implicit modifiers for proficient translation.展开更多
Epigenetic modifiers are enzymes that catalyze covalent chemical modifications on chromatin and thus play important roles in setting relatively stable states for gene expression and cell identity.It has been widely ob...Epigenetic modifiers are enzymes that catalyze covalent chemical modifications on chromatin and thus play important roles in setting relatively stable states for gene expression and cell identity.It has been widely observed that mutations in epigenetic modifiers cause various types of human diseases,such as developmental defects and cancers.Therefore,deciphering how the mutations affect functions of the epigenetic modifiers in developmental and pathological conditions is crucial for understanding the underlying mechanisms and for identifying potential therapeutic targets.展开更多
基金supported by the National Natural Science Foundation of China(U23A20605)Anhui Graduate Innovation and Entrepreneurship Practice Project(2022cxcysj090)+2 种基金China Baowu Low Carbon Metallurgy Innovation Foundation(BWLCF202202)the University Synergy Innovation Program of Anhui Province(GXXT-2020-072)the Outstanding Youth Fund of Anhui Province(2208085J19).
文摘Steel slag(SS)accumulates unavoidably due to its complex and unstable composition,high production volumes,and limited value-added resource utilization.Single or multiple interface modifiers were proposed to enhance the properties of SS through high-speed dispersion,transforming its inherent hydrophilic and oleophobic characteristics into hydrophily and lipophilicity.The modification effects were innovatively assessed by observing the color changes of modified steel slag solutions following the dissolution-settlement equilibrium constant.This approach avoided human-induced errors and improved estimated accuracy in conformance with conventional methods such as oil absorption value,activation index,sedimentation volume,and lipophilicity.The hydrolysis of 3-aminopropyltriethoxysilane(KH)generated–Si(OH)_(3)structure to form hydrogen or covalent bonds with active substances(OH groups)from SS.Concurrently,SS underwent encapsulation via Si–O–Si structure resulting from the dehydration of–Si(OH)_(3).The stearic acid coupling agent(SA),aluminate coupling agent(AC),and titanate coupling agent(TN)underwent chemical reactions with Ca(OH)_(2),Al(OH)_(3),and CaCO_(3)in SS.The acidic SA primarily created stable chemical bonds and acted as a supplement due to its package,reducing surface activity and hydrophilicity while enhancing lipophilicity.Specifically,the optimal modification effect was obtained at 3 wt.%SA.Consequently,3 wt.%SA was established as the benchmark for multiple modifiers and the most effective combination was 3 wt.%SA and 3 wt.%AC.Compared with a single interface modifier,SA corroded the SS surface to provide numerous active sites for further modification by KH,AC,or TN,resulting in a more densely packed structure.In addition,more organic groups on SS prevent the proximity of other particles from agglomerating to achieve dispersion and a synergistic modification,laying a theoretical foundation of SS in a new pathway for organic composite materials.
基金Project(2022YFC3902703)supported by the National Key R&D Program of ChinaProject(KF22028)supported by the Special Project for High Quality Development of the Ministry of Industry and Information Technology of China+1 种基金Project(62004143)supported by the National Natural Science Foundation of ChinaProject(2022BAA084)supported by the Key R&D Program of Hubei Province,China。
文摘The excessive demand for phosphorus-based fertilizers is contributing to the undesired byproduct of phosphogypsum(PG),typically found in large quantities in phosphoric acid industry.Without proper management,this industrial waste poses a significant environmental pollution risk.Current technologies are struggle to effectively handle the volume of PG produced,but one promising solution is its conversion into hemihydrate gypsum(CaSO_(4)·0.5 H_(2)O,HH).HH can exist in two phases,α-HH andβ-HH,withα-hemihydrate gypsum(α-HH)being preferred for its complete crystal structure and lower water requirement for hydration.The morphology ofα-HH gypsum is crucial for its material applications,and controlling crystal morphology is possible through the use of suitable crystal modifiers.This review explores various aspects of crystal modifiers and highlights their role in the preparation ofα-HH from PG.It suggests that leveraging the interfacial properties of PG could lead to innovative applications.Additionally,the review outlines future directions for PG development and identifies challenges to be addressed in the next steps.
文摘The effect of combining different organic friction modifiers(OFMs)with ashless dispersants on the dispersion performance of lubricant oils in sludge was investigated using molecular dynamics(MD)simulations.polyisobutylsuccinimide(PIBSI)was mixed with either glycerol monooleate(GMO)or oleamide(OAM)in a poly-α-olefin(PAO)base oil.The distribution and interaction energy of sludge precursors were analyzed both with and without these additive mixtures.The results show that both the OFMs and dispersants can form hydrogen bonds with sludge precursor molecules,preventing further aggregation.Adding OFMs to lubricant oil-containing dispersants enhances the dispersion of the lubricant.Compared to OAM,GMO forms more hydrogen bonds with sludge precursors,which favors improved dispersion.However,there is strong competition and interaction between GMO and PIBSI,which reduces the dispersant’s effectiveness in mitigating sludge precursor aggregation.The interactions among additives and their impact on performance should be considered when designing high-performance lubricant formulations.
基金Supported by the Harbin Technology Tackle Key Plan (Development Research of Wood-Polymer Composites with High Wood Matrix) and by Heilongjing Nature Science Fund (Composite Mechanism Study of the Wood Polymer).
文摘Wood-polymer composites (WPC) were prepared from wood fiber and four kinds of plastics such as PE, PS, ABS, and SAN. The effects of different modifiers on the mechanical properties of the composites were studied. The results showed modifiers could raise the bonding strength of wood fiber with polymer and improve the mechanical properties of the composites. Different modifiers had different effects on the properties of wood-polymer composites, and comparatively the modifier of isocyanate produced a better result. Wood-polymer composite takes not only the advantages of both wood fiber and polymer, but waterproof, dimensional stability and dynamic strength are also significantly improved. Key word Wood fiber - Thermoplastic polyester - Wood-polymer composites - Modifier - Mechanical properties CLC number TB332 Document code A Foundation item: This study was supported by the Harbin Technology Tackle Key Plan (Development Research of Wood-Polymer Composites with High Wood Matrix) and by Heilongjing Nature Science Fund (Composite Mechanism Study of the Wood Polymer).Biography: XU Min (1963-), Female, Associate professor in Material Science and Engineering College, Northeast Forestry University, Harbin 150040, P. R. China.Responsible editor: Chai Ruihai
基金Supported by Department of Biotechnology,New Delhi,India.No.BT/PR26150/MED/12/768/2017.
文摘X-linked adrenoleukodystrophy(X-ALD),an inborn error of peroxisomalβ-oxidation,is caused by defects in the ATP Binding Cassette Subfamily D Member 1(ABCD1)gene.X-ALD patients may be asymptomatic or present with several clinical phenotypes varying from severe to mild,severe cerebral adrenoleukodystrophy to mild adrenomyeloneuropathy(AMN).Although most female heterozygotes present with AMN-like symptoms after 60 years of age,occasional cases of females with the cerebral form have been reported.Phenotypic variability has been described within the same kindreds and even among monozygotic twins.There is no association between the nature of ABCD1 mutation and the clinical phenotypes,and the molecular basis of phenotypic variability in X-ALD is yet to be resolved.Various genetic,epigenetic,and environmental influences are speculated to modify the disease onset and severity.In this review,we summarize the observations made in various studies investigating the potential modifying factors regulating the clinical manifestation of X-ALD,which could help understand the pathogenesis of the disease and develop suitable therapeutic strategies.
文摘The effects of plasticizers,antioxidants and burning rate modifiers on the aging performance of the composite solid propellant based on hydroxyl-terminated polybutadiene(HTPB)/hexamethylene diisocyanate(HMDI)were explored by apply-ing an accelerated aging program for 90 day at 70 ℃. The HTPB propellant matrix with the diisooctyl sebacate(DOS)as plasti-cizers and diisooctyl azelate(DOZ), antioxidants as N,N ′-Diphenyl-p-phenylenediamine(AO) and 2,2′-methylenebis(4-methyl-6-tert-butylphenol)(cyanox 2246)and burning rate modifiers as barium ferrite(BF),copper chromites(CC)and fer-ric oxide(FO)were varied. Results show that sample(S1)which based on DOS decreases the stress value and increases the strain value which considered to be an excellent start for aging program. Sample(S3)containing AO presents the higher resis-tance to oxidation showing the better performance that reflects on increasing the shelf life of the composite solid propellant mo-tor. Sample(S5)which based on BF enhances the ballistic performance among over the other tested two samples. The accelerat-ed aging program allowed us to estimate the motor in-service lifetime.
文摘It is important to understand the mechanism and implications of different modifiers on analytical and preparative processes under chromatography with supercritical fluids (SFs) and under extraction with SFs. Supercritical fluid chromatography (SFC) and supercritical fluid extraction are generally carried out with neat supercritical carbon dioxide (SCCO2) or with SCCO2 containing modifiers (or cosolvents), especially for strongly polar compounds. For example, methanol is added as a cosolvent/modifier to SCCO2 for the extraction/separation of polar compounds. This paper discusses the influence of the modifier on the colligative properties of the principal mobile phase, which may define the situation in the total mobile phase in a chromatography column or in parts of a column under SFC. No colligative behavior of solutions reflects individual properties of the solutes. Their cross-interactions with solvents are discussed.
文摘Modifiers have a broad array of influences on extraction with liquids in standard state, supercritical fluid extraction (SFE), trapping by SFE and supercritical fluid chromatography (SFC). They can significantly change the qualitative and quantitative results. Quantitative and qualitative results can be influenced by different extractants and modifiers in different ways as it was shown by Brondz et al. at 2007 in “The real nature of the indole alkaloids in Cortinarius infractus: Evaluation of artifact formation through solvent extraction method development”, J. Chromatography A, 1148, 1-7. The choice of correct extractant, modifier, and trapper to the bulk mobile phase for supercritical fluids (SFs) or for liquids in subcritical or in the liquids in standard state is a challenge in any extraction procedure. This is the second paper in a sequence that describes the influence of extractants and modifiers on the performance of SFs and results of extraction with liquids in standard state and SFE. Here, attention is given to possible mistakes in qualitative and quantitative results by poor understanding of the influence of extractants, modifiers, and trappers on extraction and trapping process by a careless choice of extractant, modifier, and trapper for extraction with liquids in standard state and SFE. The SF chosen for discussion in the paper is CO2. However, similar effects can be observed with use of other SFs and fluids in subcritical and standard states. In this paper, the discussion of lipids, fatty and carboxylic acids have been chosen as target analytes for extraction, trapping and analysis. Some examples from extraction with liquids in the standard state and trapping in the supercritical state (collection) have been furnished with the wrong extractant, modifier, or trapper which is presented for illustration of inappropriate choice of extractants, modifiers, and trappers.
文摘Various of modifiers were used to modify the surface activity of white carbon black. The oil absorption, viscosity, hydrophobic rate and burning loss of white carbon black and the mechanical propertiess of silicone rubber were measured. The influences of the modifiers on the properties of white carbon black and the mechanical properties of silicone rubber were discussed.
基金the Key Scientific and Technological Project of Sichuan Province(No.03GG021-002)
文摘Using SrC12-6H2O and Na2CO3 as the main raw materials and adding different complexons as modifiers with simple co-precipitation method, SrCO3 crystals with distinct morphologies like spherical, bundle-like, overlapping plate-like, hexagonal star-like, dumbbell-like, etc. can be synthesized in the ethanol-water mixtures. The samples were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and Fourier transform infrared spectrograph （FT-IR）. The interrelated effect mechanism is presented in the end. Results show that the modifier carboxyl groups play a significant role in controlling the SrCO3 crystal morphologies, which can alter the crystal growth unit （Sr^2＋） supply mode and induce the crystal formation with the morphologies matching their spatial configurations.
基金Funded by National Natural Science Foundation of China(No.51801058)the Special Program for Guiding Local Science and Technology Development by the Central Government of Hubei Province(No.2019ZYYD006)Hubei Provincial Natural Science Foundation of China(No.2018CFB759)。
文摘The effects of modifiers on the anti-wetting and anti-icing property of the prepared rough aluminum surface were investigated.The rough aluminum substrates were obtained through electrochemical oxidization with 15 wt% sulfuric acid solution as the electrolyte at the constant current of 4 mA for 3 h.And then they were modified with octadecanoic acid (C18),polyethylene (PE),polystyrene (PS),polyethylene glycol (PEG) and hexamethylenetetramine (HMTA),respectively,whose surface free energies were 27.6,31.0,33.0,61.6 and 70.0 mN/m,respectively.The contact angles (CA) were 154.6°,128.4°,127.6°,5.0° and 0.0°,respectively,and the ice adhesion pressures were 15.9,36.3,55.9,155.3 and 216.1 kPa,respectively.The ice adhesion strengths decrease along with the increasing anti-wetting property of aluminum surfaces and the decreasing of the surface energy of modifiers.These provide some new insights when designing the aluminum surface with anti-icing properties in some special applications.
基金Sponsored by the National Natural Science Foundation of China (Grant No. 50008005)
文摘In order to verify the influence of different block proportions S/B on the effect of SBS modified asphalt,the dynamic mechanical performance test and static loading test were performed on the samples composed of different kinds of SBS with base asphalt. It is found that different S/B values fix on different modified effects and different viscoelastic mechanical behaviors,due to biphasic separate fabric of polybutadiene and polystyrene in SBS. In low-speed running pavement,the modified asphalt with lower S/B value shows better pavement performance,while in high-speed running pavement,the modified asphalt with higher S/B value shows better pavement performance. As far as SBS modified asphalt itself is concerned,mixing proportion impacts on resisting displacement and block proportion S/B ratio impacts on strain recovery capacity. In the case that the conditions are the same,SBS modified asphalt with different S/B values can be used for different travelling speed pavement construction demands to get an intelligent use.
基金supported by European Union’s Horizon 2020 research and innovation programme in the project In2Track2 under Grant agreement No. 826255
文摘By modifying friction to the desired level,the application of friction modifiers(FMs)has been considered as a promising emerging tool in the railway engineering for increasing braking/traction force in poor adhesion conditions and mitigating wheel/rail interface deterioration,energy consumption,vibration and noise.Understanding the effectiveness of FMs in wheel–rail dynamic interactions is crucial to their proper applications in practice,which has,however,not been well explained.This study experimentally investigates the effects of two types of top-of-rail FM,i.e.FM-A and FM-B,and their application dosages on wheel–rail dynamic interactions with a range of angles of attack(AoAs)using an innovative well-controlled V-track test rig.The tested FMs have been used to provide intermediate friction for wear and noise reduction.The effectiveness of the FMs is assessed in terms of the wheel–rail adhesion characteristics and friction rolling induced axle box acceleration(ABA).This study provides the following new insights into the study of FM:the applications of the tested FMs can both reduce the wheel–rail adhesion level and change the negative friction characteristic to positive;stick–slip can be generated in the V-Track and eliminated by FM-A but intensified by FM-B,depending on the dosage of the FMs applied;the negative friction characteristic is not a must for stick–slip;the increase in ABA with AoA is insignificant until stick–slip occurs and the ABA can thus be influenced by the applications of FM.
基金The Swedish International Development Cooperation Agency
文摘Reflector edges, sharp acceptance angles and by-pass diodes introduce large variations in the electrical performance of asymmetrical concentrating photovoltaic/thermal modules over a short incidence angle interval. It is therefore important to quantify these impacts precisely. The impact on the electrical performance of the optical properties of an asymmetrical photovoltaic/thermal CPC-collector was measured in Maputo, Mozambique. The measurements were carried out with the focus on attaining a high resolution incidence angle modifier in both the longitudinal and transversal directions, since large variations were expected over small angle intervals. A detailed analysis of the contribution of the diffuse radiation to the total output was also carried out. The solar cells have an electrical efficiency of 18% while the maximum measured electrical efficiency of the collector was 13.9 % per active glazed area and 20.9 % per active cell area, at 25 °C. Such data make it possible to quantify not only the electrical performance for different climatic and operating conditions but also to determine potential improvements to the collector design. The electrical output can be increased by a number of different measures, e.g. removing the outermost cells, turning the edge cells 90°, dividing each receiver side into three or four parts and directing the tracking, when used, along a north-south axis.
文摘Poly (vinyl chloride)/ethylene-vinyl acetate/montmorillonite (PVC/EVA/OMMT) composites were prepared by melt blending method. Two kinds of montmorillonites were organically modified by trimethyloctadecyl ammonium and dimethyl bis (hydrogenated tallow) ammonium, respectively. The morphology and tensile properties of the resultant composites were discussed in terms of the modifier type and OMMT content. The PVC/EVA/OMMT composites have intercalated structure, which is independent of the polarity of the modifiers, while the tensile properties show strong dependence on the modifier type. The OMMT modified by polar modifier gives higher tensile ductile and strength of PVC/EVA/OMMT composites.
基金Funded by the Natural Science Foundation of Guangdong Prov ince(013013) and the Science and Technology Plan of Guangdong Province(2002B11604)
文摘The integrated absorption cross section Σ abs, peak emis sion cross section σ emi, Judd-Ofeld intensity parameters Ω t(t=2,4,6), and spontaneous emission probability A R of Er 3+ ions were determined fo r Erbium doped alkali and alkaline earth phosphate glasses. It is found the comp ositional dependence of σ emi is almost similar to that of Σ abs, wh ich is determined by the sum of Ω t (3Ω 2+10Ω 4+21Ω 6). In addition, the compositional dependence of Ω t was studied in these glass systems. As a resu lt, compared with Ω 4 and Ω 6, the Ω 2 has a stronger compositional depend ence on the ionic radius and content of modifiers. The covalency of Er-O bonds in phosphate glass is weaker than that in silicate glass, germanate glass, alumi nate glass, and tellurate glass, since Ω 6 of phosphate glass is relatively la rge. A R is affected by the covalency of the Er 3+ ion sites and correspon ds to the Ω 6 value.
基金This work was supported by National Natural Science Foundation of China (No.59771011).
文摘The modification effect of CX-type (CX means the modifiers that have longeffective term) modifiers applied in ZL108 and ZL104 Al-Si alloys has been studied in detail. Theresults show that the morphologies of the eutectic silicon and the primary silicon can be modifiedand refined simultaneously. The modification effect acts quickly and can maintain a period of 8 h bythe CX-type modifiers. The CX-type modifiers increase the mechanical properties of Al-Si alloys andimprove the service properties of machine parts made of Al-Si alloys (such as piston and cylinderetc.). In modifying processes, the amount of the addition of CX-type modifiers is smaller than thatof any other modifiers, and the modifying procedures are simple. There are no smoke, no dust, and noirritant smell in modifying processes using CX-type modifiers. Therefore, the CX-type modifiershave advantages in economy and environment protection.
文摘There are both premodifiers and postmodifiers English noun phrases.Premodifiers and postmodifiers can be change able along with the adjustments of human cognition.It discusses the cognitive foundation of transformation between postmodifi ers and premodifiers in English noun phrases so as to find out the cognitive reason behind linguistic structure.
基金supported bythe National Social Sciences Foundation of China(No.19BYY123).
文摘This research aims to investigate the correlation between translators’construal of implicit modifiers in Chinese political chunks and their performance in target English translation.Five major types of the explicitation of Chinese implicit modifiers in English translation have been found,namely,zero,varied,partial,identical,and mixed ones.In addition,significant differences were found between student and expert translators in construing and manifesting the implicit modifiers in Chinese ST.These findings shed light on bilingualeducation in Chinese universities and the importance of raising awareness of implicit modifiers for proficient translation.
文摘Epigenetic modifiers are enzymes that catalyze covalent chemical modifications on chromatin and thus play important roles in setting relatively stable states for gene expression and cell identity.It has been widely observed that mutations in epigenetic modifiers cause various types of human diseases,such as developmental defects and cancers.Therefore,deciphering how the mutations affect functions of the epigenetic modifiers in developmental and pathological conditions is crucial for understanding the underlying mechanisms and for identifying potential therapeutic targets.
