制浆材综纤维素和聚戊糖含量的近红外预测

用传统方法测定了156个制浆材样品的综纤维素和聚戊糖含量并采集了样品的近红外光谱。对原始光谱进行多元散射校正后,运用偏最小二乘法和交互验证的方法,确定最佳主成分数分别为9和10并建立样品综纤维素和聚戊糖含量的校正模型。独立验证中两个模型的决定系数R_(val)~2分别为0.903 4、0.940 1,预测均方根误差(RMSEP)分别为0.69%、0.78%,相对分析误差(RPD)值分别为3.22、4.09,绝对偏差(AD)分别为-1.00%~1.20%、-1.39%~1.31%,两个校正模型较好地预测了验证集样品的综纤维素和聚戊糖含量,基本满足制浆造纸工业中快速测定的需求。     

近红外光谱法快速检测腐竹中硼砂的含量

选取市售腐竹作为研究对象，采集样品的近红外光谱，用国标分光光度法测定样品中硼砂的含量作为标准值，结合偏最小二乘法，建立了腐竹中硼砂含量的近红外光谱快速检测模型。结果表明，采用二阶导数谱，在7 150.75～5 924.25 cm^-1光谱区间，经多元散射校正、五点平滑处理建立的模型为较优模型。该模型的校正集线性相关系数(R_c)值为0.994 1,校正集均方根偏差(RMSEC)值为0.050 8,验证集线性相关系数(R_p)值为0.980 6,验证集均方根偏差(RMSEP)值为0.114,主因子数(factors)为10,相对分析误差(RPD)为5.1。模型有较好的稳定性，外部验证结果准确，可以用于腐竹中硼砂含量的快速检测。     

甲醛交联聚乙烯醇/麦草碱木质素发泡材料的降解性能

研究了化学降解、热降解、生物降解及紫外光降解等对甲醛交联聚乙烯醇（PVA）/麦草碱木质素发泡材料（PLFM）的力学性能和表观密度等物理性能的影响,采用红外光谱（FT-IR）、扫描电子显微镜（SEM）和热重分析（TG/DTG）等方法探讨了降解前后PLFM结构的变化。结果表明：当PLFM中碱木质素质量分数为20%时,经化学、热（150℃）、生物及紫外光降解后,拉伸强度由22.64MPa分别降为5.65、9.05、7.43和7.64 MPa,降解率分别为75.09%、60.02%、67.18%、66.25%。SEM图表明,化学降解和生物降解对PLFM闭孔结构破坏严重,紫外光降解和热降解对PLFM闭孔破坏轻微。化学降解和生物降解后,表观密度从0.183 7g/cm³分别增加到0.216 4g/cm³和0.210 4g/cm³;紫外光降解和热降解后,表观密度分别从0.183 7 g/cm³降为0.177 4和0.176 6 g/cm³。此外,FT-IR和TG/DTG分析表明：经化学、热、生物及紫外光降解后PLFM分子结构均有不同程度破坏,化学降解对PLFM结构的破坏最为严重。     

运用近红外光谱分析煤质硫含量

为了研究煤质的硫含量,采集了120个煤粉样品的近红外漫反射光谱,建立了偏最小二乘回归结合不同光谱预处理方法的定量数学模型,并与工业检测结果进行对比。结果表明:采用5点平滑处理后的模型效果最佳,相关系数达到0.89695,校正集均方根误差(RMSEC)和预测集均方根误差(RMSEP)分别为0.0406和0.0423,结果表明模型具有较高的相关性、稳定性和预测能力。     

近红外光谱法检测氨纶中残存DMAC溶剂含量

以丙酮为溶剂,将氨纶中的残存溶剂N,N'-二甲基乙酰胺(DMAC)进行超声萃取,采用近红外光谱技术,结合偏最小二乘法,建立DMAC定量校正模型,测定氨纶中残存DMAC溶剂含量。结果表明:采用交叉验证得到了DMAC质量分数的线性范围为0~1.79%,1.79%~9.44%,模型的相关系数(R~2)分别为0.999 96,0.999 64,校正集的交叉验证均方根误差分别为0.004 11,0.041 34,预测集的均方根误差分别为0.003 95,0.032 30,方法的加标回收率为86.58%~100.87%,相对标准偏差为0.25%~0.95%。     

激光诱导击穿光谱结合RFE-GBDT算法定量分析稀土矿石中的Fe和Y

稀土矿组成复杂，对选矿技术要求较高，寻找一种快速检测分析稀土矿石中元素的方法对稀土矿选矿具有重要意义。激光诱导击穿光谱(Laser-induced Breakdown Spectroscopy, LIBS)是检测稀土矿石中元素的一种重要手段，可以进行现场分析，无需制备复杂样品。建立了一种基于LIBS结合递归特征消除(Recursive Feature Elimination, RFE)和梯度提升树(Gradient Boosting Decision Tree, GBDT)算法的模型对稀土矿石中Fe元素和Y元素进行快速定量分析。采用激光诱导击穿光谱仪对25个样品进行光谱采集，将采集的光谱进行预处理后使用5折交叉验证对RFE阈值进行优化，再通过贝叶斯搜索对GBDT模型参数进行优化，构建了RFE-GBDT校正模型，对稀土矿石中的Fe和Y进行了定量分析并与真实值进行对比，结果表明，Fe和Y的预测决定系数(R_P²)分别为0.957 1和0.930 7,预测均方根误差(RMSEP)分别为0.072 7和0.022 6,说明该模型具有良好的预测性能，可以...     

近红外光谱技术在中药栀子渗漉液理化指标快速分析中的应用研究

用声光可调滤光器(AOTF)-近红外(NIR)光谱法在线分析栀子渗漉液密度及栀子苷含量。在线收集栀子渗漉液样品,建立栀子渗漉液的含量、比重数据库,同时采集近红外光谱图谱,用偏最小二乘(PLS1)法分别建立NIR光谱与含量、比重数据之间的校正模型,并对在线过程中收集的预测集样品进行含量预测来验证所建模型。结果表明,渗漉液NIR光谱与含量、比重数据之间的校正模型相关系数R2分别为0.956 0和0.978 2,外部样品预测平均相对偏差分别为0.09%,2.84%;该方法精密度RSD分别为0.06%,2.96%;稳定性RSD分别为0.63%,1.89%;预测回收率分别为100.0%,99.9%。近红外光谱技术在栀子渗漉液密度及淫羊藿苷含量分析中具有快速、直接、多成分同时测定,并能实现现场分析。     

拉曼光谱用于CHO细胞培养液多指标快速分析

为了快速分析中国仓鼠卵巢(CHO)细胞培养液,在CHO细胞培养过程中取样,离线分析获得葡萄糖浓度、乳酸浓度、谷氨酸浓度、谷氨酰胺浓度、活细胞密度、总细胞密度、细胞活度和单克隆抗体表达量等指标的参考值,采集细胞培养液上清的拉曼光谱,以偏最小二乘(PLS)法建立拉曼光谱与各指标的多元校正模型。各模型均具有合理的主成分数、较高的决定系数(R~2)、较低的校正误差均方根(RMSEC)和预测误差均方根(RMSEP),且RMSEC与RMSEP相差不大,模型具有较好的预测性能。结果表明,该方法可望用于CHO细胞培养过程多指标离线快速检测,也为该生产过程在线实时监测和反馈控制的实现提供了研究基础。     

超低密度凝胶堵剂的制备与评价

针对哈拉哈塘油田大水体发育的储层条件,以聚丙烯酰胺为主剂制备了一种超低密度(0.88～0.95 g/cm³)凝胶堵剂。探究了聚合物、密度调节剂M4对体系密度和增强剂Z3、密度调节剂M4对成胶强度的影响。结果表明：当体系加入密度调节剂时,体系密度可从1.2 g/cm³降为0.88 g/cm³,同时密度调节剂M4对体系强度有明显增强作用,无密度调节剂M4时屈服应力只有42 Pa,密度调节剂M4质量分数为4%时,屈服应力为284 Pa。     

木屑制备高孔隙成型活性炭及Doehlert设计法优化

以木屑为原料,不添加任何黏结剂,使用H₃PO₄作为活化剂,制备高孔隙的成型活性炭。利用N₂吸附-脱附、XRD及万能试验机,考察了不同活化时间（1~3 h）、活化温度（500~700 ℃）对成型活性炭性能的影响。结果表明：制备的成型活性炭具有较高的比表面积、孔隙率、得率、表观密度、耐压强度和总孔容积。在活化温度为600 ℃,活化时间为1 h的条件下,其比表面积达1 022.6 m²/g,得率为32.2 %,表观密度为0.62 g/cm³,耐压强度为5.23 MPa,总孔容积为0.49 cm³/g,微孔比例达到91.8 %。通过Doehlert设计法对反应条件进行优化,结果表明优化的制备条件为活化温度590 ℃,活化时间2.1 h,此时成型活性炭得率、耐压强度和表观密度分别为31.8 %、5.54 MPa、0.87 g/cm³。理论值和实验值存在很好的一致性,表明该理论模型是可靠的。     

甲基异丙基甲酮-苯酚-对苯二酚-水的液液相平衡数据测定、模型关联及萃取过程模拟

液液相平衡测定为溶剂萃取及回收的准确模拟、设计和过程开发提供基础数据。以甲基异丙基甲酮为萃取剂,在处理高浓煤化工含酚废水的三元液液相平衡萃取基础上,选定其中典型单元酚苯酚和多元酚对苯二酚为代表物,测定甲基异丙基甲酮-苯酚-对苯二酚-水在常压40℃下的液液相平衡数据。采用NRTL和UNIQUAC活度系数模型对实验数据进行热力学关联,回归得到该四元体系的二元交互作用参数。结果表明该模型可以很好地关联实验数据,两种模型的相对均方根偏差分别小于0.190%和0.266%。进一步将得到的二元交互参数导入流程模拟系统,对萃取单元模块进行计算。当萃取温度40℃、萃取级数5级、相比1：7.72时,甲基异丙基甲酮能将总酚12700 mg×L^-1,多元酚4250 mg×L^-1的含酚废水的酚浓度分别降低至300 mg×L^-1和299 mg×L^-1以下。     

Enhance hydrates formation with stainless steel fiber for high capacity methane storage

In order to realize efficient gas storage of hydrate, stainless steel fiber (SSF) was added to 0.03% (mass) sodium dodecyl sulfate (SDS) solution for gas storage experiment. SSF can not only improve the problem that hydration heat cannot be removed effectively in the hydration process, but also improve gas storage speed and gas storage by increasing hydrate nucleation sites. Under the experimental conditions (273.2 K, 5-9 MPa), the peaks of temperature rise in SDS + SSF systems were found to become much smaller than those in SDS systems. The maximum gas storage rate and the maximum methane uptake of SSF + SDS system reached 9.89-24.90 cm³·g^-1·min^-1 and 178.65-200.89 cm³·(g H₂O)^-1, respectively. Compared with the surfactant SDS solution without SSF, they increased by 10.47%-33.22% and 9.16%-25.36%, respectively. The effect of SSF length on gas storage performance was studied. Due to the continuous thermal conduction network, longer SSF showed a higher gas storage capacity and methane uptake rate compared with shorter SSF. At the same time, compared with other metal fillers, SSF + SDS not only had excellent gas storage performance, but also the amount of SSF (0.1 g·ml^-1) was only 7.6% of foamed aluminum, and the volume gas storage density was increased by 145.4%. The use of stainless steel fiber made the best use of the thermal conductivity of metal, reduced the amount of metal used, and improved the volume density and mass density of gas storage.     

PHBV/PLA纤维和其他纤维混合试样的定量分析方法研究

采用化学分析和红外光谱分析相结合的方法研究了生物基聚3-羟基丁酸-戊酸酯/聚乳酸(PHBV/PLA)纤维和其他纤维(涤纶、棉纤维、羊毛、锦纶6)混合的试样(简称多组分混合纤维试样)的定量分析方法。结果表明:首先在常温条件下,采用二氯甲烷溶解多组分混合纤维试样中的PHBV/PLA纤维,得到PHBV/PLA纤维的含量和其他纤维的含量,该方法的绝对误差为-0.5%~0.5%,95%置信界限为(-0.2%,0.2%);然后选定合适溶剂对多组分纤维混合试样中的其他纤维进行溶解得到PHBV/PLA纤维,对PHBV/PLA纤维中的PHBV和PLA的含量采用红外光谱法进行定量分析,将1707.2~1731.8 cm^-1的峰面积和1731.8~2038.8 cm^-1峰面积之比作为PHBV和PLA组分的对应质量比,以此来计算试样中PHBV和PLA的含量,该方法采用经典最小二乘法建立模型,7个校准点拟合的回归方程其线性相关系数为0.9978,校正标准偏差为0.442;10个验证点拟合的回归方程的线性相关系数为0.9943,预测标准偏差为0.617%。     

硅/巯基复合改性光固化WPUA涂料制备及其性能

采用端羟基硅油（HS）、季戊四醇四-3-巯基丙酸酯（PETMP）先后改性紫外光固化水性聚氨酯丙烯酸酯（WPUA）,探究了HS及PETMP添加量对涂膜性能的影响。FTIR表征了改性前、后产物的结构;测试了乳液粒径,并利用TEM和SEM对乳液形貌和涂层断面进行了分析。通过涂膜附着力、硬度、柔韧性、抗冲击、接触角、综合热分析、电化学阻抗谱及极化曲线等测试评价涂层的机械性能、疏水性、耐热性及防腐性能。结果表明：当HS及PETMP添加量分别为3%、5%时,硅/巯基复合改性的紫外光固化WPUA涂层相对于改性前,硬度由HB提升为3H,附着力由3级提升到1级,柔韧性为0.5mm,耐冲击为50cm,接触角由68.5°提升到90.5°,吸水率由18.78%降低为6.94%;涂层的热稳定性显著增强;涂层阻抗由1.86×10⁶Ω·cm²增大到6.45×10⁷Ω·cm²,E_coor由 -1.069V正移到-0.4215V,I_coor由2.12×10^-8A/cm²减小到8.11×10^-10A/cm²,年腐蚀速率为0.0242mm。表明HS及PETMP的引入显著提升了涂层的综合性能。     

介孔纳米氧化铝的制备、表征及其应用

Using aluminum isopropoxide as the aluminum source and O,O′-bis(2-aminopropyl) polypropylene glycol-block-polyethylene glycol-block-polypropylene glycol as the template,ordered worm-like mesoporous nano-alumina was prepared by sol-gel method.The characterization results showed that the surface area,average pore diameter and pore volume of the calcined mesoporous alumina were 341.1 m²·g^-1,17.4 nm and 1.54 cm³·g^-1,respectively.The catalytic properties of the mesoporous nano alumina for the dehydration of isopropanol to propylene was investigated.The results indicated that the as-prepared mesoporous nano-alumina exhibited high catalytic activity.The conversion of isopropanol and the selectivity to propylene were more than 99.0% and 98.5%,respectively,when isopropanol WHSV was 0.5 h^-1,1.0 h^-1 and 2.0 h^-1 and the corresponding reaction temperature was controlled at the range of (230-320) ℃,(250-340) ℃ and (260-350) ℃,respectively.     

Sublimation Pressure and Sublimation Coefficient of Single-Crystal Lead Selenide

The torsion-Langmuir and torsion-effusion methods, respectively, were used to study the sublimation characteristics of oriented single-crystal and powdered lead selenide. Analysis of the data showed that the sublimation coefficient is unity over the experimental range. From combined free-surface and equilibrium data the expression for the sublimation pressure of PbSe from 887° to 1052°K was found to be log P(atm) =- (1.226±0.015) 10⁴/T+(8.163±0.154), where T is the absolute temperature and the errors are standard deviations. Third-law calculations of the heat of sublimation at 298°K gave 55.66±0.20 kcal/mol PbSe.     

A comparison of the attachment of the decay products of radon-220 and radon-222 to monodispersed aerosols

The adsorption of radioactive aerosols is of prime importance when assessing the hazard of inhalation of radioactive materials, especially in the uranium mining industry. In previous studies of the attachment rate, contradicting results on the dependence on particle size have been found. The attachment rate for the attachment of the decay products of Rn-222 to monodispersed polystyrene aerosols (of a diameter from 1.2 to 5.3 μm) in the concentration range 1–67 particles cm⁻³ was measured directly. This is compared with the attachment rate of radon-220 decay products which was measured in a previous experiment. As before, the attachment between the radioactive atoms and the aerosols was found to be directly proportional to the particle concentration N, as well as to the square of the particle radius R.

The attachment coefficient of 4.1 × 10⁵ R² cm³ min⁻¹ and the sticking probability of 0.13 for Rn-222 decay products were found to be larger than that for the decay products of Rn-220 (2.4 × 10⁵ R² cm³ min⁻¹ and 0.08, respectively). The mechanism for the attachment, however, is the same.     

Kinetics of asphaltenes conversion during hydrotreating of Maya crude

The kinetics of asphaltene conversion was studied during the hydrotreating of Maya heavy crude oil. Experimental tests were conducted in a pilot plant at the following reaction conditions: total pressure of 70–100 kg/cm², liquid hourly space-velocity (LHSV) of 0.33–1.5 h⁻¹, and reaction temperature of 380–420 °C at a constant hydrogen-to-oil ratio of 5000 ft³/bbl. A commercial NiMo/Al₂O₃ catalyst was used in all experiments. Asphaltenes were precipitated from Maya crude and from hydrotreated products in a Parr Batch Reactor at 25 kg/cm² and 60 °C with n-heptane as solvent. Asphaltene hydrocracking data were used to estimate reaction orders and activation energy using a power-law model, and the average absolute error between experimental and calculated concentrations of asphaltenes was found to be less than 5%.     

Effect of Microstructure on Ferroelectric and Piezoelectric Properties of A-Site and B-Site Modified PLZT

Ba modified (Pb,La,Ag)(Zr,Ti)O₃ ceramics synthesized by conventional mixed-oxide method with chemical formula [Pb_{0.983 - z}La_0.012Ag_0.005Ba_z] [(Zr_0.52Ti_0.48)_0.99825]O₃ were investigated for ferroelectric and piezoelectric properties. XRD studies indicate that increment of Ba concentration resulted in strong tetragonality in the ceramics. Grain growth (3.08 μ m) inhibited and apparent density (7.54 gm/cm³) enhanced up to 1.5 mole% Ba respectively. As Ba content increased dielectric properties showed maximum values (ε_RT = 2347, ε_Tc = 23449) while T_c constantly decreased. The remanent (P_r = 34.72 μ C/cm²) and spontaneous polarization (P_s = 41.84 μ C/cm²) were optimum in 1 mole% Ba respectively while E_c showed increasing trend throughout the series. Piezoelectric properties attained maximum values of d₃₃ = 438 pC/N in 1.5 mole% Ba while k_p = 0.533 and k_t = 0.412 in 1 mole% Ba doped (Pb,La,Ag)(Zr,Ti)O₃ ceramics respectively.