Acaricidal effect of the antimicrobial metabolite xenocoumacin 1 on spider mite control

The two-spotted spider mite,Tetranychus urticae Koch,is one of the most harmful pests in many agroecosystems worldwide.To effectively manage this pest,there is an urgent need to develop novel bio-active acaricides that support integrated pest management strategies targeting T.urticae.In this study,we explored the acaricidal effects of xenocoumacin 1 (Xcn1) on T.urticae and its predator Neoseiulus californicus using the highly puri?ed compound.Xcn1 was extracted and purified from the cell-free supernatant of the Xenorhabdus nematophila CB6 mutant constructed by the easy promoter activated compound identi?cation (easyPACId) method.When the concentration of Xcn1 exceeded 100μg mL~(–1),the survival rate of spider mite adults declined to below 40%and the fecundity was decreased by 80%at six days post-application.At concentrations of 25 and 50μg mL~(–1),Xcn1 signi?cantly impeded spider mite development by inhibiting the molt.However,neither concentration had any adverse effects on the survival or reproduction of the predatory mite N.californicus.The results from laboratory and semi-?eld experiments consistently demonstrated the effectiveness of the antimicrobial metabolite Xcn1 in controlling pest mites at both the molecular and physiological levels.Our study offers a promising possibility that combines the compatible biocontrol agents of Xcn1 and predatory mites for integrated pest mite control.

Dendrobium officinale extract exerts antioxidant effects against skin photoaging through MMP9-TNF pathway

Background:Skin photoaging is a physiological or pathological process caused by multiple factors.Developing anti-skin photoaging drugs is a hot topic in cosmetology research fields.The purpose of this study was to explore the therapeutic effect of Dendrobium officinale(D.officinale)on skin aging.Methods:The ingredients of D.officinale were detected by UHPLC-Q-TOF/MS.The targets of D.officinale were screened by Swiss Target Prediction database.GeneCards,NCBI,and OMIM databases were utilized to find out the targets associated with skin photoaging.Overlapping targets of D.officinale and skin photoaging were obtained by Venn analysis.The ingredient-disease target network and protein-protein interaction network were constructed by using the STRING database and Cytoscape software.The key compounds and hub genes were obtained by analyzing networks.The DAVID database was applied for Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis of the overlapping targets.Autodock Vina software was used to simulate molecular docking and the results were visualized using Pymol.Finally,the skin photoaging models of cells and mice were established to validate the results predicted by network pharmacology.Results:In D.officinale,a total of 59 compounds and 595 targets were detected,of which 59 proteins were intersectional with skin photoaging targets.The top 10 active ingredients(Dendrophenol,Herbacetin,Lyoniresinol,Trans-ferulaldehyde,Naringenin,and so on)and 8 hub genes(AKT1,TNF,VEGFA,MAPK3,CASP3,MMP9,CTNNB1,and EGFR)were identified.All the key active compounds could bind well with core protein targets(binding energy<-5 kcal/mol).The potential therapeutic targets were related to the response to reactive oxygen species,collagen catabolic process,extracellular matrix organization,and apoptotic process,mainly.We also found that D.officinale could enhance the cell viability and activity of anti-oxidases,reduce reactive oxygen species and MMP9 levels,and stable mitochondrial membrane potential.Furthermore,D.officinale could alleviate skin photoaging injury and reduce malondialdehyde level in mice.Conclusion:D.officinale alleviated skin photoaging via regulating oxidative stress,apoptosis,and collagen catabolic process.

Preparation of activated carbon from cattail and its application for dyes removal

Activated carbon was prepared from cattail by H3PO4 activation. The effects influencing the surface area of the resulting activated carbon followed the sequence of activated temperature 〉 activated time 〉 impregnation ratio 〉 impregnation time. The optimum condition was found at an impregnation ratio of 2.5, an impregnation time of 9 hr, an activated temperature of 500℃, and an activated time of 80 min. The Brunauer-Emmett-Teller surface area and average pore size of the activated carbon were 1279 m^2/g and 5.585 nm, respectively. A heterogeneous structure in terms of both size and shape was highly developed and widely distributed on the carbon surface. Some groups containing oxygen and phosphorus were formed, and the carboxyl group was the major oxygen-containing functional group. An isotherm equilibrium study was carried out to investigate the adsorption capacity of the activated carbon. The data fit the Langmuir isotherm equation, with maximum monolayer adsorption capacities of 192.30 mg/g for Neutral Red and 196.08 mg/g for Malachite Green. Dye-exhausted carbon could be regenerated effectively by thermal treatment. The results indicated that cattail-derived activated carbon was a promising adsorbent for the removal of cationic dyes from aqueous solutions.

Ultraviolet spectral broadening by stimulated rotational Raman scattering on nitrogen pumped with signal laser injection

We present experimental results on kilojoule ultraviolet laser output with 1%spectral broadening.Through stimulated rotational Raman scattering(SRRS)with signal laser injection,we achieve effective spectral broadening in short-range propagation,with good retention of the original near-field distribution and time waveform.Theoretical calculations show that 2%bandwidth spectral broadening can be achieved by injecting 20 kW~cm^(2) signal light at 2.2 GW~cm^(2) flux of the pump laser.In addition,high-frequency modulation in the near field can be effectively avoided through replacement of the original random noise signal light by the controllable signal light.The SRRS in the atmospheric environment excited with signal laser injection can provide wide-band light output with controllable beam quality without long-distance propagation,representing an important potential route to realization of broadband laser drivers.

Effects of pore size and porosity of surface-modified porous titanium implants on bone tissue ingrowth

The effects of surface-modified porous titanium implants with different porosities and pore sizes on osseointegration were investigated in vivo.Three porous titanium implants(A30,A40 and A50 containing volume fractions of space-holder NaCl being 30%,40%and 50%,respectively)were manufactured by metal injection moulding(MIM).The surface-modified implants were implanted into muscles and femurs of hybrid male dogs.Interface osteogenic activity and histological bone ingrowth of porous titanium implants were evaluated at 28,56 and 84 d.The results showed that when additive space-holder amount of NaCl increased from 30%to 50%(volume fraction),the general porosity and mass fraction of macropores of porous titanium rose from 42.4%to 62.0%and from 8.3%to 69.3%,respectively.Histologic sections and fluorescent labeling showed that the A50 implant demonstrated a significantly higher osteogenic capacity at 28 d than other implants.Bone ingrowth into the A30 implant was lower than that into other implants at 84 d.Therefore,the pore structure of A50 implant was suitable for new bone tissue to grow into porous implant.

Zinc finger E-box-binding homeobox 1 mediates aerobic glycolysis via suppression of sirtuin 3 in pancreatic cancer

AIM TO uncover the roles of tumor-promoting gene ZEB1 in aerobic glycolysis regulation and shed light on the underlying molecular mechanism.METHODS Endogenous zinc finger E-box binding homeobox-1 （ZEB1） was silenced using a and the impact of ZEB1 and lentivirus-mediated method, methyI-CpG binding domain protein 1 （MBD1） on aerobic glycolysis was measured using seahorse cellular flux analyzers, reactive oxygen species quantification, and mitochondrial membrane potential measurement. The interaction between ZEB1 and MBD1 was assessed by co-immunoprecipitation and immunofluorescence assays. The impact of ZEB1 and MBD1 interaction on sirtuin 3 （SIRT3） expression was confirmed by quantitative polymerase chain reaction, western blotting, and dual-luciferase and chromatinimmunoprecipitation assays.RESULTS ZEB1 was a positive regulator of aerobic glycolysis in pancreatic cancer. ZEB1 transcriptionally silenced expression of SIRT3, a mitochondrial-localized tumor suppressor, through interaction with MBD1.CONCLUSION ZEB1 silenced SIRT3 expression via interaction with MBD1 to promote aerobic glycolysis in pancreatic cancer.

数智赋能智慧教育的变与不变之道

数智技术的出现,为教育带来新的可能性,将持续推动教育领域的深刻变革。在数智技术赋能教育数字化转型的背景下,智慧教育代表着未来教育发展的趋势。智慧教育借助数智技术的力量,跨越传统课堂教学的界限,引领着教育领域向全新的学习模式和教育观念转变。基于这样的时代背景,厘清技术影响下教育的发展规律,探讨数智赋能智慧教育的变与不变之道,有助于数智技术高效地推动教育的向好发展。首先,解构教育数字化转型背景下教育的变与不变,厘清这个问题,有助于教育从业者更好地坚守初心、把握机遇、顺应变革。然后,在深入论述智慧教育带来教育之变的基础上,探讨智慧教育的未来范式,即人机协同学习、高意识学习、智慧学习生态化和新质人才培养范式。最后,提出应对数智时代教育变革的策略:教育契约从集权管理向民主治理转变;教育文化从自囿因袭向开放创新转变;思维品质从固化心态向成长心态转变;教学模式从教为中心向学为中心转变;教育目标从知识本位向能力本位转变;供需关系从供给主导向需求主导转变;教育规制从阶段学习向终身学习转变;教育架构从谱系结构向泛在生态转变。

Recombinant Tissue Plasminogen Activator-conjugated Nanoparticles Effectively Targets Thrombolysis in a Rat Model of Middle Cerebral Artery Occlusion

The efficacy and safety of recombinant tissue plasminogen activator （rtPA） need to be improved due to its low bioavailability and requirement of large dose administration. The purpose of this study was to develop a fibrin-targeted nanoparticle （NP） drug delivery system for thrombosis combination therapy. We conjugated rtPA to poly（ethylene glycol）- poly（ε-caprolactone） （PEG-PCL） nanoparticles （rtPA-NP） and investigated its physicochemical characteristics such as particle size, zeta potential, enzyme activity of conjugated rtPA and its storage stability at 4℃. The thrombolytic activity of rtPA-NP was evaluated in vitro and in vivo as well as the half-life of rtPA-NP, the properties to fibrin targeting and its influences on systemic hemostasis in vivo. The results showed that rtPA-NP equivalent to 10% of a typical dose of rtPA could dissolve fibrin clots and were demonstrated to have a neuroprotective effect after focal cerebral ischemia as evidenced by decreased infarct volume and improved neurological deficit （P〈0.001）. RtPA-NP did not influence the in vivo hemostasis or coagulation system. The half-life of conjugated rtPA was shown to be approximately 18 times longer than that of free rtPA. These experiments suggested that rtPA-conjugated PEG-PCL nanoparticles might be a promising fibrin-targeted delivery system for a combination treatment of thrombosis.

Incorporating topographic factors in nonlinear mixed-effects models for aboveground biomass of natural Simao pine in Yunnan,China

A total of 128 Simao pine trees （Pinus kesiya var. langbianensis） from three regions of Pu＇er City, Yunnan Province, People＇s Republic of China, were destructively sampled to obtain tree aboveground biomass （AGB）. Tree variables such as diameter at breast height and total height, and topographical factors such as altitude, aspect of slope, and degree of slope were recorded. We considered the region and site quality classes as the ran- dom-effects, and the topographic variables as the fixed- effects. We fitted a total of eight models as follows： least- squares nonlinear models （BM）, least-squares nonlinear models with the topographic factors （BMT）, nonlinear mixed-effects models with region as single random-effects （NLME-RE）, nonlinear mixed-effects models with site as single random-effects （NLME-SE）, nonlinear mixed-ef- fects models with the two-level nested region and site random-effects （TLNLME）, NLME-RE with the fixed-ef- fects of topographic factors （NLMET-RE）, NLME-SE with the fixed-effects of topographic factors （NLMET-SE）, and TLNLME with the fixed-effects of topographic factors （TLNLMET）. The eight models were compared by modelfitting and prediction statistics. The results showed： model fitting was improved by considering random-effects of region or site, or both. The models with the fixed-effects of topographic factors had better model fitting. According to AIC and BIC, the model fitting was ranked as TLNLME 〉 NLMET-RE 〉 NLME-RE.〉 NLMET-SE 〉 TLNLMET 〉 NLME-SE 〉 BMT 〉 BM. The differences among these models for model prediction were small. The model pre- diction was ranked as TLNLME 〉 NLME-RE 〉 NLME- SE 〉 NLMET-RE 〉 NLMET-SE 〉 TLNLMET 〉 BMT 〉 BM. However, all eight models had relatively high prediction precision （〉90 %）. Thus, the best model should be chosen based on the available data when using the model to predict individual tree AGB.

Efficacy of irinotecan-based chemotherapy after exposure to an anti-PD-1 antibody in patients with advanced esophageal squamous cell carcinoma

Objective:Several anti-programmed cell death 1(anti-PD-1)antibodies have demonstrated potential efficacy in the treatment of advanced esophageal squamous cell cancer(ESCC).However,the response to subsequent chemotherapy after the failure of PD-1 blockade in ESCC patients has not been reported,and the optimal sequencing of immunotherapy and chemotherapy remains controversial.The aim of the present study was to evaluate responses to irinotecan-based subsequent chemotherapy in advanced ESCC patients who had progressed after treatment with camrelizumab(SHR-1210),a novel anti-PD-1 antibody.Methods:We retrospectively reviewed the medical records of patients with advanced ESCC treated with camrelizumab at a single institution.Consecutive patients who received subsequent irinotecan-based chemotherapy were selected for data collection and analysis.Results:Overall,a total of 28 patients were included.All patients had received at least two lines of systemic treatment prior to irinotecan salvage.The most common regimen that was administered after PD-1 blockade was irinotecan in combination with 5-fluorouracil(5-Fu)(or its derivatives),which was given to 19 patients.The objective response rate(ORR)and disease control rate(DCR)were 17.9%(5/28)and 64.3%(18/28),respectively,with 5(17.9%)patients achieving a partial response and 13(46.4%)having stable disease.The median progressionfree survival(PFS)was 3.18[95%confidence interval(95%CI),2.48-3.88]months and the median overall survival(OS)was 6.23(95%CI,4.71-7.75)months.No new safety issues,either immune-related or otherwise,were observed.Conclusions:Our results suggested that the response to irinotecan-based chemotherapy after PD-1 blockade in advanced ESCC patients appeared similar to that previously observed in patients who had not received PD-1 antibodies,and further study in larger cohorts or randomized trials is warranted to verify our observation.

Effect of CXCR4 pretreated with ultrasound-exposed microbubbles on accelerating homing of bone marrow mesenchymal stem cells to ischemic myocardium in AMI rats

Objective: To investigate the role and potential mechanism of CXCR4 in promoting targeted homing of bone marrow mesenchymal stem cells(BMSCs) with ultrasound-exposed microbubbles(UM) pretreatment. Methods: Third generation BMSCs were divided into four groups control group, ultrasound(US) group, UM group and ultrasound-exposed microbubbles plus catalase group. RT-PCR and western blot were performed to determine the levels of CXCR4 m RNA transcription and protein expression, respectively. Third generation BMSCs were labeled with Fluo-α/AM and divided into three groups: control group, US group and UM group, and flurorescence intensities in the cells were observed immediately, 5 min and 15 min after intervention underflurorescence microscope. The calcium iron levels in the cells were analyzed. BMSCs were divided into i ve group: group A without calcium in the medium, group B, group C, group D and group E containing calcium chloride with concentration of l mol, 2 mol, 4mol, anti-calciurn-sensing receptor antibody, respectively. RT-PCR and western blot were performed to determine the levels of CXCR4 m RNA transcription and proteins expression of the third generation BMSCs of each group, respectively. Results: The levels of CXCR4 m RNA transcription and protein expression between US group and control group had no statistically signii cant dif erence(P>0.05) shown by RT-PCR and western blot; the transcription level in the UM group was signii cantly higher than that in US group and control group(P<0.05); and in the ultrasound-exposed microbubbles plus catalase group, the transcription level was much lower than that in UM group. Fluorescence intensify in the cells of US group had no signii cant dif erence compared with that in the cells of the control group(P>0.05), which in the cells of UM group was signii cantly higher than that in the cells of both US group and control group(P<0.05). Compared to group A, expressions of CXCR4 of group B to D were signii cantly increased in concentration-dependent manner showed by RT-PCR and western blot(P< 0.05). Compared to group C, expressions of CXCR4 of group E were signii cantly decreased(P< 0.05). Conclusions: UM can promote the inl ux of calcium in BMSCs and increase m RNA transcription and protein expression of CXCR4. The latter may partly be caused by influx of calcium.

Responses of Annual Variability of Vegetation NPP to Climate Variables Using Satellite Techniques in Gadarif State, Sudan

Plants play an essential role in matter and energy transformations and are key messengers in the carbon and energy cycle. Net primary productivity (NPP) reflects the capability of plants to transform solar energy into photosynthesis. It is very sensible for factors affecting on vegetation variability such as climate, soils, plant characteristics and human activities. So, it can be used as an indicator of actual and potential trend of vegetation. In this study we used the actual NPP which was derived from MODIS to assess the response of NPP to climate variables in Gadarif State, from 2000 to 2010. The correlations between NPP and climate variables (temperature and precipitation) are calculated using Pearson’s Correlation Coefficient and ordinary least squares regression. The main results show the following 1) the correlation Coefficient between NPP and mean annual temperature is Somewhat negative for Feshaga, Rahd, Gadarif and Galabat areas and weakly negative in Faw area;2) the correlation Coefficient between NPP and annual total precipitation is weakly negative in Faw, Rahd and Galabat areas and somewhat negative in Galabat and Rahd areas. This study demonstrated that the correlation analysis between NPP and climate variables (precipitation and temperature) gives reliably result of NPP responses to climate variables that is clearly in a very large scale of study area.

Dietary methionine deficiency stunts growth and increases fat deposition via suppression of fatty acids transportation and hepatic catabolism in Pekin ducks

Background:Although methionine(Met),the first-limiting dietary amino acid,has crucial roles in growth and regulation of lipid metabolism in ducks,mechanisms underlying are not well understood.Therefore,the objective was to use dietary Met deficiency to investigate the involvement of Met in lipid metabolism and fat accumulation of Pekin ducks.Methods:A total of 150 male Pekin ducks(15-d-old,558.5±4.4 g)were allocated into 5 groups(6 replicates with 5 birds each)and fed corn and soybean meal-based diets containing 0.28%,0.35%,0.43%,0.50%,and 0.58%Met,respectively,for 4 weeks.Met-deficient(Met-D,0.28%Met)and Met-adequate(Met-A,0.43%Met)groups were selected for subsequent molecular studies.Serum,liver,and abdominal fat samples were collected to assess the genes and proteins involved in lipid metabolism of Pekin ducks and hepatocytes were cultured in vivo for verification.Results:Dietary Met deficiency caused growth depression and excess fat deposition that were ameliorated by feeding diets with adequate Met.Serum triglyceride and non-esterified fatty acid concentrations increased(P<0.05),whereas serum concentrations of total cholesterol,low density lipoprotein cholesterol,total protein,and albumin decreased(P<0.05)in Met-D ducks compared to those in Met-A ducks.Based on hepatic proteomics analyses,dietary Met deficiency suppressed expression of key proteins related to fatty acid transport,fatty acid oxidation,tricarboxylic acid cycle,glycolysis/gluconeogenesis,ketogenesis,and electron transport chain;selected key proteins had similar expression patterns verified by qRT-PCR and Western blotting,which indicated these processes were likely impaired.In vitro verification with hepatocyte models confirmed albumin expression was diminished by Met deficiency.Additionally,in abdominal fat,dietary Met deficiency increased adipocyte diameter and area(P<0.05),and down-regulated(P<0.05)of lipolytic genes and proteins,suggesting Met deficiency may suppress lipolysis in adipocyte.Conclusion:Taken together,these data demonstrated that dietary Met deficiency in Pekin ducks resulted in stunted growth and excess fat deposition,which may be related to suppression of fatty acids transportation and hepatic catabolism.

Factors associated with improvement in waist-to-height ratio among newly diagnosed type 2 diabetes patients treated with acarbose or metformin:A randomized clinical trial study

BACKGROUND The waist-to-height ratio(WHtR)is a promising anthropometric measure used to evaluate cardiovascular risk in diabetes and metabolic syndrome patients.The metformin and acarbose in Chinese as the initial hypoglycaemic treatment trial demonstrated that acarbose and metformin reduced the WHtR after 24 wk of treatment.AIM To investigate the factors associated with a decrease in the WHtR in newly diagnosed Chinese type 2 diabetes patients receiving acarbose or metformin monotherapy.METHODS At 24 wk,343 patients in the acarbose treatment and 333 patients in the metformin treatment were included in this analysis.On the basis of the reduction in the WHtR,these participants were divided into the following two groups:LowΔWHtR group and highΔWHtR group.Metabolic and related parameters associated with a highΔWHtR were investigated using univariate and multivariate logistic regression analyses.RESULTS A significant decrease in the WHtR was observed in both treatment groups(acarbose:-0.015,95%confidence interval[CI]:-0.018 to-0.012,P<0.001;metformin:-0.013,95%CI:-0.016 to-0.010,P<0.001).In both the acarbose and metformin groups,the WHtR of the women was more likely to be reduced than that of the men.In the acarbose group,a lower baseline area under the curve of glucagon-like peptide 1(AUCGLP-1)was associated with a highΔWHtR(odds ratio[OR]=0.796,P<0.001),while a higher baseline AUCGLP-1 was associated with a highΔWHtR in the patients treated with metformin(OR=1.133,P=0.025).Regarding the changes from baseline,an increase in AUCGLP-1 was associated with a highΔWHtR in the acarbose(OR=1.121,P=0.016)but not metformin group.A higher reduction in high-density lipoprotein cholesterol/non-highdensity lipoprotein cholesterol was also associated with a highΔWHtR in the acarbose arm(OR=20.735,P=0.001).In the metformin arm,a higher reduction in fasting plasma glucose(OR=0.843,P=0.039)and total cholesterol was associated with a highΔWHtR(OR=0.743,P=0.013).CONCLUSION A lower glucagon-like peptide 1 level and higher increase in glucagon-like peptide 1 are associated with a high reduction in the WHtR in newly diagnosed Chinese diabetes patients receiving treatment with acarbose.

Enhancing Hydrocarbon-Rich Bio-Oil Production via Catalytic Pyrolysis Fortified with Microorganism Pretreatment

A new method of pretreatment of corn straw with Phanerochaete chrysosporium combined with pyrolysis was proposed to improve the quality of bio-oil.The characterization results demonstrated that microbial pretreatment was an effective method to decrease the lignin,which can achieve a maximum removal rate of 44.19%.Due to the destruction of biomass structure,the content of alkali metal and alkaline earth metal is reduced.Meanwhile,the depolymerized biomass structure created better pyrolysis conditions to promote the pyrolysis efficiency,increase the average decomposition rate of pyrolysis and reduce the residue.In fast pyrolysis,because of the enrichment of cellulose and the removal of lignin,the contents of acids,linear carbonyls,furans,and sugars increased while the contents of phenols decreased.As for the catalytic pyrolysis,due to the hydrocarbon pool reaction and shape selection deoxidation of ZSM-5 catalyst,the total hydrocarbon and aromatics contents can significantly increase up to 34.37%and 30.59%,respectively,with 3 weeks of pretreatment.And the the low molecular content of bio-oil increased after pretreatment,which can significantly benefit the entry of primary pyrolysis steam into the catalyst pores to improve the catalytic efficiency and hydrocarbon contents.This method provides a new treatment idea for high-quality utilization of biomass.

Kinetics Analyzing of Direction Reduction on Manganese Ore Pellets Containing Carbon

Using high temperature carbon tube furnace, reduction of manganese ore pellets containing carbon was investigated. The reaction was divided into two stages at five minutes after reaction, and the kinetics model of reduction process was established. The experimental results showed that, the reaction rate in the earlier stage was controlled by the chemical reactions between FeO, MnO and carbon reductant, and the activation energy was 28.85 KJ/mol. In the later stage, as the carbon reductant replaced by CO, the reaction rate was controlled by CO-diffusing in solid products, and the cor- responding activation energy was 86.56 KJ/mol. Reaction rate of the later stage was less than the earlier one.

Trace element partitioning between amphibole and hydrous silicate glasses at 0.6–2.6 GPa

Partitioning behavior between amphibole and silicate glass of thirty-three minor and trace elements(Sc,Ti, V, Cr, Co, Rb, Sr, P, Y, Zr, Nb, Cs, Ba, K, La, Ce, Pr,Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, Pb,Th, and U) have been determined experimentally. Products of crystallization of hydrous basalt melts from 0.6 GPa/860 °C up to 2.6 GPa/970 °C were obtained in a multianvil apparatus. Major and trace element compositions of amphibole and glass were determined with a combination of electron microprobe and laser ablation inductively coupled plasma mass spectrometry. The main mineral phase is calcic amphibole, and the coexisting glass compositions are tonalite, granodiorite, and granite. The compatibility of rare earth elements increase at 915 °C and then decrease at 970 °C, but the compatibility of most of these elements shows a continued, significant increase with increasing pressure. For high-field strength elements, large ion lithophile elements, actinide compatibility decrease with increasing temperature or pressure, but transition metals show a continued increase in compatibility within the temperature–pressure conditions. From mathematical and graphical fitting, we determined best-fit values for the ideal ionic radius(r_0, 1.01–1.04 ?), the strain-free partitioncoefficient(D_0, 1.18–1.58), and apparent Young's modulus(E, 142–370 GPa) for the M4 site in amphibole according to the lattice strain model. The D_0^(M4) for rare earth elements rises at 915 °C and then drops at 970 °C at 0.6 GPa.However, the D_0^(M4) values are positively proportional to the pressure for rare earth elements in the amphibole-glass pairs at 0.6–2.6 GPa and 970 °C. Furthermore, the derived best-fit values for r_0^(M4) and E^(M4) are almost constant and trend to increase with rising temperature and pressure,respectively. The partition coefficient is distinctly different for different melt compositions. The rare earth elements become more enriched in amphibole if the quenched glass is granodiorite or granite compared to the tonalitic glasses.

Investigation of mass transfer model of CO_(2) absorption with Rayleigh convection using multi-relaxation time lattice Boltzmann method

CO_(2) absorption into absorbents is a widely used method to reduce carbon emissions,in which the concentration gradient near the gas-liquid interface may induce Rayleigh convection(RC).Once RC occurs,the mass transfer rate will be significantly enhanced.Therefore,it is necessary to explore the mass transfer enhancement mechanism further and develop a penetration/surface divergence hybrid mass transfer model.In this study,we conduct research on the process of CO_(2) absorption into ethanol with RC.Firstly,we use a multi-relaxation time lattice Boltzmann method to simulate the absorption process and obtain the flow and concentration fields.And we also verify the reliability of the numerical simulation results by comparing with the experimental results.Then,we analyze the characteristics of non-uniform flow and concentration fields in RC.Moreover,we divide the near-interface region into diffusion-dominated and convection-dominated mass transfer zones by checking whether the horizontal average velocity is greater than 1.0×10^(-4) m·s^(-1).Furthermore,based on the differences in mass transfer mechanisms of the aforementioned two zones,we propose a penetration/surface divergence hybrid model to predict the instantaneous mass transfer coefficient.The prediction results demonstrate that the hybrid model can precisely predict the instantaneous mass transfer coefficient of the entire CO_(2) absorption process.Our proposed hybrid model provides a promising way to deal with the complex mass transfer problems with non-uniform flow and concentration fields.

A preliminary study on the acoustic properties of seafloor sediment in the southern U-boundary of the South China Sea

The acoustic properties of seafloor sediment are essential parameters in the exploration of marine resources,ocean scientific research and ocean engineering.Seafloor sediment samples were collected at the southern U-boundary of the South China Sea(SCS),and the acoustic and physical properties were measured in the laboratory.The correlation between physical and sound speed ratio(SSR)was discussed,and SSR-physical property empirical regressions in the Sunda Shelf were established for the first time.Compared with the northern continental shelf of SCS,the Sunda Shelf are mainly silty and sand sediment,and the SSR ranges from 0.9949 to 1.0944,which has higher SSR than the northern continental shelf,implies that the Sunda Shelf is a high SSR area.Since the same kind of sediment has different physical properties,the single physical parameter of sediment cannot fully represent the acoustic properties of sediment,therefore,the multiple parameter prediction model should develop in the future to improve the prediction precision.

Design of Subharmonic Mixers above 100 GHz

This paper presents the design and simulation of several fixed-tuned sub-harmonic mixers cover frequencies from 110 GH to 130 GHz, 215 GH to 235 GHz, 310 GH to 350 GHz, and 400 GH to 440 GHz. Among them, 120 GHz, 225 GHz, 330 GHz subharmonic mixers are designed with flip-chipped planar schottky diode mounted onto a suspended quartz-based substrate, the 225 GHz and 425 GHz subharmonic mixers are GaAs membrane integrated, and the 115 GHz subharmonic mixer has been fabricated and tested already.