Modeling time-dependent mechanical behavior of hard rock considering excavation-induced damage and complex 3D stress states

To investigate the long-term stability of deep rocks,a three-dimensional(3D)time-dependent model that accounts for excavation-induced damage and complex stress state is developed.This model comprises three main components:a 3D viscoplastic isotropic constitutive relation that considers excavation damage and complex stress state,a quantitative relationship between critical irreversible deformation and complex stress state,and evolution characteristics of strength parameters.The proposed model is implemented in a self-developed numerical code,i.e.CASRock.The reliability of the model is validated through experiments.It is indicated that the time-dependent fracturing potential index(xTFPI)at a given time during the attenuation creep stage shows a negative correlation with the extent of excavationinduced damage.The time-dependent fracturing process of rock demonstrates a distinct interval effect of the intermediate principal stress,thereby highlighting the 3D stress-dependent characteristic of the model.Finally,the influence of excavation-induced damage and intermediate principal stress on the time-dependent fracturing characteristics of the surrounding rocks around the tunnel is discussed.

超高效液相色谱-串联质谱法检测乳清蛋白粉中神经节苷脂GD3

建立了超高效液相色谱-串联质谱快速测定乳清蛋白中双唾液酸神经节苷脂(GD3)的方法。通过试验优化样品的初次提取条件(提取剂比例及用量)和再萃取条件(萃取剂用量)。在样品充分溶解后,用4 mL三氯甲烷-甲醇溶液(V_(三氯甲烷)∶V_(甲醇溶液)=1∶2)提取1.0 mL样液,转移合并提取液,加入2.0 mL水进行萃取转移为最佳提取条件。然后分别对质谱与色谱条件(定量扫描模式、色谱柱以及流动相pH)进行优化,选取Syncronis HILIC硅胶色谱柱,以0.01 mol/L乙酸铵水溶液-乙腈(pH5.6)为流动相,进行色谱分离,色谱分离后采用母离子监测模式定量测定和多反应监测模式定性分析。在最佳优化分析条件下,双唾液酸神经节苷脂GD3质量浓度在0.5~50.0μg/mL内具有良好的线性关系,相关系数(R^(2))>0.99,回收率在87.3%~103.7%,精密度(RSD)为4.16%~8.95%,检出限在0.1 g/kg。该方法可用于乳清蛋白粉中双唾液酸神经节苷脂GD3。

Gd^(3+)/Ce^(3+)对Tb^(3+)掺杂氟氧化物玻璃发光敏化作用的影响

本文采用高温熔融法制备了Gd/Tb、Gd/Ce、Gd/Ce/Tb掺杂的SiO_(2)-B_(2)O_(3)-BaF_(2)组分氟氧化物玻璃,通过测试X射线衍射光谱确定了其物相,通过测试其不同波段激发下的荧光光谱研究了不同Gd_(2)O_(3)掺量下Tb^(3+)的发光性能,并确定了Gd_(2)O_(3)更精确的最佳掺量范围。此外,文中通过改变气氛制备了Gd/Ce/Tb共掺杂氟氧化物玻璃,对比研究了Gd^(3+)和Ce^(3+)对Tb^(3+)的敏化作用。结果表明,本文所制备的氟氧化物玻璃都呈稳定的玻璃态;Gd^(3+)和Ce^(3+)对Tb^(3+)的发光都具有敏化作用,且Gd_(2)O_(3)掺量为7%(摩尔分数,下同)时敏化效果相较于其他掺量最为显著,超出7%则造成猝灭;Ce_(2)O_(3)掺入玻璃后以Ce^(3+)和Ce^(4+)两种价态共存,在还原气氛下掺入相较于空气气氛下掺入更容易保持Ce^(3+)状态,而且Ce^(3+)对Tb^(3+)的发光具有敏化作用,Ce^(4+)会抑制Tb^(3+)的发光。

Cardioprotective Potential of Cymbopogon citratus Essential Oil against Isoproterenol-induced Cardiomyocyte Hypertrophy:Possible Involvement of NLRP3 Inflammasome and Oxidative Phosphorylation Complex Subunits

Objective:Cymbopogon citratus(DC.)Stapf is a medicinal and edible herb that is widely used for the treatment of gastric,nervous and hypertensive disorders.In this study,we investigated the cardioprotective effects and mechanisms of the essential oil,the main active ingredient of Cymbopogon citratus,on isoproterenol(ISO)-induced cardiomyocyte hypertrophy.Methods:The compositions of Cymbopogon citratus essential oil(CCEO)were determined by gas chromatography-mass spectrometry.Cardiomyocytes were pretreated with 16.9µg/L CCEO for 1 h followed by 10µmol/L ISO for 24 h.Cardiac hypertrophy-related indicators and NLRP3 inflammasome expression were evaluated.Subsequently,transcriptome sequencing(RNA-seq)and target verification were used to further explore the underlying mechanism.Results:Our results showed that the CCEO mainly included citronellal(45.66%),geraniol(23.32%),and citronellol(10.37%).CCEO inhibited ISO-induced increases in cell surface area and protein content,as well as the upregulation of fetal gene expression.Moreover,CCEO inhibited ISO-induced NLRP3 inflammasome expression,as evidenced by decreased lactate dehydrogenase content and downregulated mRNA levels of NLRP3,ASC,CASP1,GSDMD,and IL-1β,as well as reduced protein levels of NLRP3,ASC,pro-caspase-1,caspase-1(p20),GSDMD-FL,GSDMD-N,and pro-IL-1β.The RNA-seq results showed that CCEO inhibited the increase in the mRNA levels of 26 oxidative phosphorylation complex subunits in ISO-treated cardiomyocytes.Our further experiments confirmed that CCEO suppressed ISO-induced upregulation of mt-Nd1,Sdhd,mt-Cytb,Uqcrq,and mt-Atp6 but had no obvious effects on mt-Col expression.Conclusion:CCEO inhibits ISO-induced cardiomyocyte hypertrophy through the suppression of NLRP3 inflammasome expression and the regulation of several oxidative phosphorylation complex subunits.

Fluorescence Properties of Eu^(3+)/Gd^(3+)/Citric Acid Mixed Complexes Doping in Silicon Rubber Matrix

Series of doped rare earth compiexes-EuxGd(1-x) (CA)3·nH2O (CA = citric acid) were synthesized. Some characterizations were taken for these complexes. The experimental results shows that the doped rare earth complexes have the best fluorescence property when the ratio of Eu and Gd is from 0.7 to 0.3. Silicon rubber-based composites were prepared by mechanical blending the EuxGd(1-x) (CA)3·nH2O and silicon rubber. Then, the fluorescent property of the composites was studied. It is found that the fluorescence intensity of the composites increase linearly with the contents of the rare earth complexes increasing.

Er^(3+),Yb^(3+)∶Ba_(3)Gd(PO_(4))_(3)晶体的生长、光谱和1.5μm激光性能

采用提拉法生长了1.85%Er,23.95%Yb∶Ba_(3)Gd(PO_(4))_(3)和1.95%Er,55.73%Yb∶Ba_(3)Gd(PO_(4))_(3)两种晶体(式中Er、Yb浓度为原子数分数)。测量并分析了晶体在室温下的吸收系数谱、上转换荧光谱、发射截面谱、增益截面谱和荧光衰减曲线。1.85%Er,23.95%Yb∶Ba_(3)Gd(PO_(4))_(3)晶体在峰值荧光波长1537 nm处的发射截面、Er^(3+)的4 I 13/2多重态荧光寿命和Yb^(3+)→Er^(3+)的能量传递效率分别为0.54×10^(-20)cm^(2)、9.9 ms和90%;1.95%Er,55.73%Yb∶Ba_(3)Gd(PO_(4))_(3)晶体在峰值荧光波长1537 nm处的发射截面、Er^(3+)的4 I 13/2多重态荧光寿命和Yb^(3+)→Er^(3+)的能量传递效率则分别为0.58×10^(-20)cm^(2)、9.7 ms和93%。基于975 nm半导体激光端面泵浦,在1.85%Er,23.95%Yb∶Ba_(3)Gd(PO_(4))_(3)晶体中实现了97 mW最高功率和27.1%斜效率的1567 nm连续激光输出,在1.95%Er,55.73%Yb∶Ba_(3)Gd(PO_(4))_(3)晶体中实现了93 mW最高功率和17.1%斜效率的1567 nm连续激光输出。

血清HBD-3、DCR3对复杂性肾结石患者经皮肾镜碎石术后尿路感染的预测价值

目的分析血清β-防御素-3(HBD-3)、诱骗受体3(DCR3)对复杂性肾结石患者经皮肾镜碎石术后尿路感染的预测价值。方法选取2020年1月—2022年12月河北省沧州中西医结合医院收治的112例复杂性肾结石患者为研究对象进行回顾性研究,所有患者均行经皮肾镜碎石术(PCNL),根据术后感染情况将患者分为非尿路感染组52例、尿路感染组60例。比较两组一般资料及HBD-3、DCR3水平。受试者工作特征(ROC)曲线分析C反应蛋白(CRP)、降钙素原(PCT)、HBD-3、DCR3水平对术后尿路感染的预测价值。结果与非尿路感染组比较,尿路感染组的HBD-3[(0.77±0.08)ng/mL vs.(1.36±0.25)ng/mL,P=0.001]、DCR3[(4.68±0.53)ng/mL vs.(13.21±0.28)ng/mL,P=0.001]水平较高。多因素logistics回归分析显示,泌尿道手术史、术前尿路感染、手术时间、导尿管留置时间、结石负荷、抗菌药物种类、合并肾功能障碍、术中通道类型CRP、PCT、HBD-3、DCR3为患者术后尿路感染的影响因素(P<0.05)。ROC曲线显示,CRP、PCT、CRP联合PCT准确度分别为70.54%、72.32%、78.57%;HBD-3、DCR3、HBD-3联合DCR3准确度分别为69.64%、75.89%、86.61%。结论复杂性肾结石患者术后尿路感染与多种因素相关,且术后尿路感染患者HBD-3、DCR3表达水平较高,联合检测对术后尿路感染具有较高的预测价值。

小核RNA激活复合体多肽3基因rs4741506多态性与中国汉族人群缺血性脑卒中及其中医证候的相关性分析

目的探讨中国汉族人群中小核RNA激活复合体多肽3(SNAPC3)基因rs4741506多态性与缺血性脑卒中(IS)及其中医证候的关系。方法选取2016年1月至2019年12月在广西中医药大学第一附属医院脑病科住院治疗的774例IS患者作为观察组,同期本院体检中心的健康体检者以及医院骨科轻症外伤患者793例作为对照组。对IS患者进行中医证候辨证,对SNAPC3基因多态性位点rs4741506进行基因分型检测。建立4种遗传模型,应用PLINK软件和SPSS 21.0软件进行遗传关联及基因位点多态性与IS及其中医证候和患者临床指标的相关性分析。结果观察组与对照组rs4741506位点的基因型频率分布差异有统计学意义(χ^(2)=6.366,P=0.041)。在加性模型、显性模型、隐性模型中,SNAPC3基因rs4741506多态性与IS的发生风险均无显著相关性(均P>0.05)。多因素Logistic回归模型分析结果显示,校正年龄和性别后SNAPC3基因rs4741506多态性与IS风证(隐性模型:比值比=0.45,95%置信区间:0.22~0.92,P=0.029)、痰证(隐性模型:比值比=0.39,95%置信区间:0.19~0.81,P=0.011)发生风险相关,而与血瘀证的发生风险无明显相关性(显性模型:比值比=1.42,95%置信区间:1.00~2.01,P=0.051)。在隐性模型下,校正年龄和性别后SNAPC3基因rs4741506多态性与IS痰证患者舒张压水平相关(β=-10.93,95%置信区间:-20.64~-1.22,P=0.028)。一般线性回归分析结果显示,校正年龄和性别后SNAPC3基因rs4741506多态性与IS痰证患者血清载脂蛋白A1(加性模型、显性模型)、载脂蛋白B(隐性模型)、血小板计数(加性模型、显性模型)水平、凝血酶时间(显性模型)显著相关(均P<0.05)。结论SNAPC3基因rs4741506多态性可能影响IS风证及痰证的发生发展。

深圳沙河水质净化厂及3#调蓄池工艺设计要点及特点

沙河水质净化厂设计规模为旱季10万m^(3)/d,雨季额外处理10万m^(3)/d初期雨水,3#调蓄池设计规模为15.3万m^(3)。污水及初期雨水处理采用预处理+多段厌氧-好氧(AO)+二沉池+磁混凝高效沉淀池+精密过滤+紫外消毒的工艺,出水水质执行深圳市地方标准《水质净化厂出水水质规范》(DB 4403/T 64—2020)B级标准,其中总氮(TN)≤8 mg/L。污泥处理采用离心浓缩+低温热干化工艺,处理后含水率≤40%。作为国内首个将水质净化厂与初期雨水调蓄池深度融合的全地下式水污染治理综合体,项目采用多段AO耦合“3W法”(Wet-Weather-Wastewater法),并以此为核心提出了一种实现大规模污水及初期雨水高标准协同处理的系统解决方案,且无需大幅度增加污水处理设施体量、投资和运行成本。

Fabrication of Gd_(2)O_(3)-doped CeO_(2)thin films through DC reactive sputtering and their application in solid oxide fuel cells

Physical vapor deposition(PVD)can be used to produce high-quality Gd_(2)O_(3)-doped CeO2(GDC)films.Among various PVD methods,reactive sputtering provides unique benefits,such as high deposition rates and easy upscaling for industrial applications.GDC thin films were successfully fabricated through reactive sputtering using a Gd_(0.2)Ce_(0.8)(at%)metallic target,and their application in solid oxide fuel cells,such as buffer layers between yttria-stabilized zirconia(YSZ)/La0.6Sr0.4Co0.2Fe0.8O_(3−δ)and as sublayers in the steel/coating system,was evaluated.First,the direct current(DC)reactive-sputtering behavior of the GdCe metallic target was determined.Then,the GDC films were deposited on NiO-YSZ/YSZ half-cells to investigate the influence of oxygen flow rate on the quality of annealed GDC films.The results demonstrated that reactive sputtering can be used to prepare thin and dense GDC buffer layers without high-temperature sintering.Furthermore,the cells with a sputtered GDC buffer layer showed better electrochemical performance than those with a screen-printed GDC buffer layer.In addition,the insertion of a GDC sublayer between the SUS441 interconnects and the Mn-Co spinel coatings contributed to the reduction of the oxidation rate for SUS441 at operating temperatures,according to the area-specific resistance tests.

Al_(2)O_(3f)/Mg-6Al-1Nd-1Gd复合材料的显微组织及时效行为

采用维氏显微硬度计、扫描电镜(SEM)、能谱仪(EDS)和X射线衍射仪(XRD)等研究了Al_(2)O_(3f)/Mg-6Al-1Nd-1Gd复合材料的显微组织和时效行为。结果表明:复合材料的组织主要由α-Mg、Al_(2)O_(3)、β-Mg_(17)A1_(12)、Mg_(2)Si、MgO、Al_(2)Nd、Al_(2)Gd以及Al_(11)Nd_(3)相组成。Al_(2)O_(3)短纤维的引入加速了基体合金的时效动力学,使基体合金的时效峰值时间由32 h显著缩短至24 h。时效过程中,β-Mg_(17)Al_(12)相主要以连续析出和非连续析出两种形式析出,连续析出和非连续析出的生长呈竞争关系,随着时效时间的增加,非连续析出相逐渐长大并由晶界向晶粒内部推移,过时效阶段晶粒内部出现成片的非连续析出相。

Gd^(3+)取代及十二面体空位对石榴石铁氧体高功率低损耗特性的影响

采用传统陶瓷工艺制备足量和缺量Gd^(3+)取代的钇铁石榴石铁氧体,研究通过缺量Gd^(3+)取代在十二面体位(24c)引入空位对材料显微结构、饱和磁化强度、铁磁共振线宽、自旋波线宽、居里温度、电阻率等性能的影响。研究表明,24c空位可促进了烧结阶段的致密化过程和晶粒生长。通过适量引入24c空位,铁磁共振线宽从154 Oe减小到64 Oe,自旋波线宽从9.7 Oe提高到24.4 Oe。空位的存在还增强了16a位与24d位Fe^(3+)之间的超交换作用,提高了材料的居里温度。另外,空位对铁氧体材料电阻率影响不大,使其具备优异的介电性能。

Gd^(3+)和In^(3+)联合取代对石榴石铁氧体高功率低损耗特性的影响

采用传统陶瓷工艺制备Gd^(3+)和In^(3+)取代的钇铁石榴石铁氧体,研究Gd^(3+)和In^(3+)取代对材料显微结构、饱和磁化强度、铁磁共振线宽、自旋波线宽、电阻率等性能的影响。研究表明,Gd^(3+)取代24c位的Y^(3+),对样品显微结构、居里温度和电阻率无明显影响。随着Gd^(3+)取代量的增加,自旋波线宽从9.7 Oe提高到21.7 Oe。为了降低石榴石铁氧体损耗,采用适量的In^(3+)取代16a和24d位的Fe^(3+),铁磁共振线宽从198 Oe减小到95 Oe。此外,In^(3+)取代对石榴石铁氧体的电阻率、介电常数和介电损耗影响不大,使其保持良好的介电性能。

Gd^(3+)掺杂对白光LED用Y_(2.88)Al_(5)O_(12):Ce^(3+)荧光粉性能的影响

采用化学共沉淀法一次煅烧工艺制备了Y_(2.88-x)Gd_(x)Al_(5)O_(12):0.06Ce^(3+)(x=0~0.5)系列荧光粉,研究了Gd^(3+)掺杂对制备的荧光粉样品的晶体结构、发光性能和光色性能的影响。研究结果表明:Gd^(3+)掺杂没有改变样品晶体结构,晶胞参数先减小后增大;其激发光谱分布在320~520 nm,激发峰位于340 nm和450 nm处,可被蓝光InGaN芯片有效激发;在450 nm蓝光激发下,发射光谱强度先增大后减小,光谱峰位从533 nm红移到542 nm,色坐标点向白光坐标曲线移动。

Synthesis,Structure and Dielectric Properties of a Novel 3D Gd(Ⅲ)Complex{[Gd(HPIDC)·(μ_4-C_2O_4)_(0.5)·H_2O]·2H_2O}_n

Under hydrothermal conditions, 2-（pyridin-4-yl）-lH-imidazole-4,5-dicarboxylaic acid （H3PIDC） reacted with Gd（NO3）3 to give a 3D complex {[Gd（HPIDC）＇a-C204）0.5＂H20]＂ 2H20}n （1）. Single-crystal X-ray determination shows that complex 1 crystallizes in the monoclinic system, space group P21/c with a = 8.287（8）, b = 14.796（14）, c = 11.559（11） ]k, fl = 90.969（15）, Z = 4, V = 1417（2） A3, C11H11GdN3Og, Dc = 2.280 g/cm3, Mr = 486.48, 2（MoKa） = 0.71073 A, p = 4.738 mm-1, F（000） = 936, R = 0.0248 and wR = 0.0522. Dielectric constant of complex 1 was measured at different frequencies with temperature variation.

Hydrothermal Syntheses and Crystal Structures of Cobalt(Ⅱ) Complexes Constructed by Dipyrido[3,2-a:2',3'-c]phenazine and Different Carboxylate Ligands

Two new metal-organic complexes,{[Co2（bptc）（DPPZ）2（H2O）2]·H2O}n 1 and {[Co2（ccm）2（DPPZ）2]·2H2O}n 2,were obtained by the hydrothermal reactions of Co（NO3）2·6H2O with chelating ligand dipyrido[3,2-a：2＇,3＇-c]phenazine（DPPZ） and the corresponding carboxylic acid,namely,3,3＇,4,4＇-benzophenonetetracarboxylic acid（H4bptc） or 2-carboxycinnamic acid（H2ccm）,respectively.The complexes were structurally characterized by single-crystal X-ray diffraction,elemental analyses,IR spectra,and thermal gravimetry.1 presents unique chiral chain structures,which are further consolidated into three-dimensional supramolecular frameworks via noncovalent bonds,such as hydrogen bonding and π-π interactions.2 features infinite double-chain structures,which are connected by strong π-π interactions to result in three-dimensional supramolecular architectures.

Hydrothermal Syntheses and Crystal Structures of Six Complexes Constructed from 1,3,5-Benzenetricarboxylic Acid and 4'-(4-Pyridyl)-2,2':6',2''-terpyridine Mixed Ligands

Six new transition metal complexes, [Zn（HBTC）（PYTPY）]n·n PYTPY（1）, [Cu（HBTC）（PYTPY）]n·n PYTPY（2）, [Co（HBTC）（PYTPY）]n·n DMF（3）, [Mn（HBTC）（PYTPY）]n·n DMF（4）, [Cd（HBTC）（PYTPY）（H2O）]n·2nH2O（5）, and [Co（HBTC）（PYTPY）（H2O）2]（6）,（H3BTC = 1,3,5-benzenetricarboxylic acid, PYTPY = 4＇-（4-pyridyl）-2,2＇：6＇,2＇＇-terpyridine, DMF = N,N？-dimethylformamide）, have been synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. Complexes 1~5 all feature one-dimensional chain structures, and complex 6 exhibits a zero-dimensional structure. Complexes 1~5 present three-dimensional（3D） supramolecular frameworks via π-π stacking interactions, whenas 6 has also a 3D supramolecular structure assembled by hydrogen bonding. Meanwhile, complexes 1 ~ 6 exhibit the thermal stabilities and photoluminescent properties.

Synthesis and properties of Tb^(3+) isomultiligand complexes

Four kinds of terbium containing monomers were synthesized by the reaction of Tb isoproxides with acrylic acid and β diketones. The composition and structure of these monomers were confirmed by FT IR, UV spectroscopy and elemental analysis. DTA and TG analyses reveal that the decomposition temperature of these monomers is in the range of 190～200 ℃. The fluorescence properties of these monomers were studied. Under the excitation of UV light, these monomers exhibit characteristic luminescence of terbium ion, the fluorescent intensity is affected by the polarity of solvent and triplet state of ligand. In solid state, the monochromatic index of luminescence is enhanced.

Synthesis of 1-(2-Hydroxyphenyl)-3-Phenyl-1,3-Propanedione and Luminescence Properties of Its Europium Complexes

Using 2＇-Hydroxyacetophenone and as the raw material, 1-（ 2-Hydroxyphenyl ）-3-Phenyl-1, 3- Propanedione （HPPPD） was synthesized by esterification reaction and Fries rearrangement reaction. And the complexes of HPPPD with europium were also synthesized. The compounds were characterized by IR, thermo-gravimetric analysis and ^1H-NMR. The effects of phenolic hydroxyl on the luminescence properties of complexes were studied. The results show that the complexes emit strong red fluorescence and the fluorescence intensity of the ternary complex is better than that of the duality. But the complexes of HPPPD with Sm（ Ⅲ ）, Tb （ Ⅲ ）, Dy （ Ⅲ ） emit weak fluorescence. The phenomenon was interpreted by electron-effect and energy-matching mechanism. Energy transfer mechanism of the luminescence in the complex was discussed.