含辣素衍生结构疏水缔合聚合物的缓蚀性能研究

采用失重法、电化学方法以及表面观察方法对比研究了含辣素衍生结构疏水缔合聚合物P(AM-MAA-AMPSHDDE-SA)(PAMAHS)和聚丙烯酰胺对Q235钢在CO_2饱和的模拟油田采出水中的缓蚀性能。实验结果表明:相较于聚丙烯酰胺,PAMAHS对碳钢在油田水中的腐蚀具有较好的抑制作用,其缓蚀率随着聚合物浓度的增加而增大,缓蚀剂浓度为500mg·L~(-1)时,缓蚀效率能达到80.64%。因此,PAMAHS是一种混合抑制型缓蚀剂,其分子可以吸附在金属表面,形成一层具有保护作用的吸附膜,从而起到减缓腐蚀的作用。PAMAHS在碳钢表面的吸附行为符合Langmuir吸附等温式。     

邻苯二酚烷基化反应机理的密度泛函研究

采用密度泛函理论(DFT)B3LYP方法,在6-311G(d,p)基组下研究邻苯二酚与N-羟甲基丙烯酰胺的烷基化反应机理,对反应物、过渡态、中间体和产物进行了结构全优化和确认,通过HOMO轨道百分组成预测芳环上的反应活性位点。结果表明:邻苯二酚与N-羟甲基丙烯酰胺烷基化反应机理分四步,活化能分别是61.07、39.69、44.31和31.51J/mol。一取代反应势垒为61.07kJ/mol;二取代反应势垒为44.31kJ/mol。表明二取代反应较一取代更容易发生。另外,一取代产物芳环上活性位点碳原子所带负电荷(-0.806)高于反应物邻苯二酚芳环上的碳原子(-0.124),有利于亲电试剂进攻,说明反应更易发生二取代,这与实验结果一致。     

氨基酸在改性黏土上的吸附机制研究

研究了四种氨基酸(赖氨酸、谷氨酸、甘氨酸、组氨酸)化合物在改性黏土的吸附特征, 考察了改性剂PACl 添加比例、介质pH 及离子强度对吸附过程的影响, 并探讨了吸附机制。结果表明, 在一定比例的PACl 改性能促进氨基酸在高岭土上的吸附, 最佳改性比例为5%, 赖氨酸、谷氨酸、甘氨酸、组氨酸的最大吸附量分别为827、712.56、723.14、732.56 μmol/g; 氨基酸在改性黏土上的吸附动力学符合伪二阶动力学模型; 利用Weber-Morris 模型测定四种氨基酸内部粒子扩散常数, 5%改性条件下赖氨酸、谷氨酸、甘氨酸、组氨酸的内部粒子扩散常数分别为0.847、0.567、0.780、0.603。热力学研究表明, 氨基酸在改性黏土上的吸附等温线是C 型等温线, 5%改性条件下四种氨基酸(赖氨酸、谷氨酸、甘氨酸、组氨酸)的热力学自由能分别为?1.99、?2.41、?3.16、?2.94 kJ/mol, 说明氨基酸在改性黏土上的吸附是一个自发的吸附过程。介质pH 及离子强度对吸附过程具有重要影响。     

动力学模型预测小黄鱼(Pseudosciaena polyactis)鱼干常温保藏下的货架期

为了预测小黄鱼(Pseudosciaena polyactis)鱼干的货架期,对贮藏在30°C、35°C、40°C下的小黄鱼干的品质进行测定,通过测定菌落总数、酸价、过氧化值三个指标在贮藏期间的变化,分别对这三个指标与贮藏时间、温度建立一级动力学方程及Arrhenius方程,建立小黄鱼干货架期预测模型。经计算得出,菌落总数预测模型中的活化能(Ea)及指前因子(k0)分别为29.26kJ/mol和4.46×102,酸价预测模型中的的活化能及指前因子分别为47.05kJ/mol和4.1×105,过氧化值预测模型中的活化能及指前因子分别为49.76kJ/mol和1.53×106。在37°C和42°C条件下验证动力学模型,结果表明相对误差分别为?4.68%和?6.25%,准确性较好。进一步推算得出,在20°C和25°C常温下贮藏小黄鱼干,产品的货架期为500d和352d。     

Tween20在海洋沉积物上的吸附行为

研究非离子表面活性剂Tween20在海洋沉积物上的吸附行为.发现沉积物中有机质和粘土矿物的含量对其吸附起主要作用.在实验浓度范围内,Tween20在HCl和H2O处理沉积物上的吸附行为可用线性等温式描述,而在H2O2处理样上的吸附行为可用Freundlich等温式来描述.海水的离子强度和温度都影响其吸附行为:离子强度增加,温度降低,会使沉积物的吸附能力增加.根据热力学函数关系计算出吸附焓ΔHθ为-32.98 kJ/mol,吉布斯自由能ΔGθ为-16.01～-16.99 kJ/mol,吸附熵ΔSθ＜0.Tween20在海洋沉积物上的吸附是一自发放热的过程.     

流动注射Ferene分光光度法测定海水中溶解态铁的方法优化

热液流体中溶解态铁是海水原位测量的重要参数之一。本研究采用Ferene分光光度法,搭建流动注射分析系统,优化进样条件、显色条件,实现了热液流体中溶解态铁的在线测定。结果表明,测定Fe(II)时,Ferene、缓冲液浓度分别为8×10–3、0.4 mol/L,Ferene、样品流速分别为0.8、0.6 m L/min,显色盘管长度为40 cm时,方法的灵敏度、检测限最佳;测定Fe(III)时,Ferene、缓冲液、抗坏血酸浓度分别为1×10–2、0.5、0.01 mol/L,Ferene/抗坏血酸、样品流速均为1.0 m L/min,还原、显色盘管长度均为40 cm时,方法的灵敏度、检测限最佳。最佳实验条件下,Fe(II)、Fe(III)在0.2~10μmol/L和0.5~16μmol/L范围内,工作曲线回归方程分别为A=0.0834 C+0.0564(μmol/L,n=8,R2=0.997)和A=0.0478C+0.0423(μmol/L,n=8,R2=0.997)。Fe(II)、Fe(III)检测限分别为24、39 nmol/L,相对标准偏差分别为0.8%、1.2%(n=10),加标回收率为97.9%~103.0%。共存离子实验表明,流体中的Na+、Mn2+、Cu2+、Cu+不会对测量造成干扰。     

河口硅酸盐物理化学过程研究——Ⅲ、河口活性硅转移机理的现场验证初步研究—悬浮物中硅、铁和铝的含量分布

在本研究第二篇中,我们通过实验室模拟研究,发现海水中Fe+++或Al+++离子在适当pH条件下生成Fe(OH)₃或Al(OH)₃胶体沉淀后,对活性硅有相当大的吸附能力;同时还通过吸附热计算、淋洗脱附实验和重溶解实验,判断上述吸附并不是一般可逆的离子交换吸附,而比较可能是化学吸附,吸附后基本上不转化为高聚硅酸结构,而比较可能进行结构重排转入内部结构中去.根据这些结果,我们提出一个关于河口活性硅地球化学转移的理论图象:即活性硅主要通过由于pH和盐度提高而生成的铁、铝等元素氢氧化物胶体沉淀的吸附而转移,再进一步转化为比较稳定的铁、铝的硅酸盐化合物形式,沉积到海底.为了进一步验证这个理论图象的现实性,我们再度在九龙江口进行了一些现场取样分析研究,试图通过河口各处海水悬浮物中各化合形式硅、铁、铝的分布变化资料,加以初步归纳总结,并和理论图象相对照.     

氧化多壁碳纳米管对水中钠离子的吸附研究

本文研究了强酸(体积比为3︰1的硫酸与硝酸)氧化的多壁碳纳米管对水中钠离子的吸附特性,考察了温度、初始浓度、吸附时间对钠离子吸附的影响。实验结果表明:多壁碳纳米管对钠离子的吸附能力随温度升高而下降;其吸附过程符合Langmuir吸附等温模型,但是在钠离子浓度较高时多壁碳纳米管的吸附特性更符合Freundlich等温模型;在温度为274K条件下,多壁碳纳米管对钠离子的吸附能约为-5.53KJ/mol即-57.3meV;化学反应焓变约为-9.31KJ/mol,表明混酸氧化的多壁碳纳米管对钠离子的吸附过程基本为物理吸附。     

不同氮磷比及铁浓度对球形棕囊藻二甲基硫和二甲巯基丙酸内盐生产的影响

本文通过实验室培养研究了不同氮磷比(0∶1、5∶1、20∶1、50∶1)以及铁浓度(10、100、1 000nmol·L-1)对球形棕囊藻二甲基硫(DMS)和二甲巯基丙酸内盐(DMSP)产生的影响。富磷浓度(36.12μmol·L-1)条件下的球形棕囊藻DMS和DMSP的产量明显高于贫磷浓度条件下(0.361 2μmol·L-1)的DMS和DMSP的产量,N/P比为50∶1时球形棕囊藻的DMS和DMSP产量明显高于其他N/P比(0∶1、5∶1、20∶1)的DMS和DMSP产量,但N/P比为50∶1时单位Chl-aDMS/DMSP产量在4个N/P比(0∶1、5∶1、20∶1、50∶1)中却最低。贫磷培养液的DMSPd在N/P比为0∶1时峰值显著高于其它N/P比(5∶1、20∶1、50∶1)条件下的DMSPd,并且N/P比为50∶1时DMS的释放量最大。低Fe3+浓度有助于球形棕囊藻藻液中DMSPd的形成,Fe3+浓度为1 000nmol·L-1时单位Chl-a的DMSPp产量最小,而单位Chl-a的DMS生产能力在Fe3+浓度为100nmol·L-1时得到加强。     

海底油气管道内CO2腐蚀与防腐的研究

本工作采用2.4mV/s动态电位扫描极化、控制电位极化、电偶电流和高压釜挂片失重法研究了X60钢在含Ca~(2+)36.26mg/L,Mg~(2+)12.66mg/L和Cl~-3624mg/L的模拟氯化钠盐水中,CO_2引起腐蚀的电化学行为,以及含氮、硫的有机缓蚀剂和(或)Me~(2+)对腐蚀的抑制作用。结果表明:溶有CO_2的盐水腐蚀性强,盐浓度及温度会影响钢的腐蚀速度和阴极极化行为;75mg/L缓蚀剂的缓蚀率达90％,服从Langmuir吸附等温式;50mg/L缓蚀剂与127mg/LMe~(2+)复配,缓蚀率达91％以上,不服从Langmuir吸附等温式。     

Kinetic simulation of hydrocarbon generation from lacustrine type I kerogen from the Songliao Basin: Model comparison and geological application

Eight lacustrine Type I kerogen samples from the Songliao Basin were pyrolyzed using the Rock-Eval equipment, and parallel first-order reaction models including the model with a single frequency factor and a discrete distribution of activation energies (SFF model) and the model with multiple frequency factors and a discrete distribution of activation energies (MFF model) were adopted to analyze kinetic characteristics of hydrocarbon generation of the Type I kerogen samples. The results show that the MFF and SFF models can satisfactory simulate hydrocarbon generation under laboratory conditions and the Type I kerogen shows relatively concentrated activation energy distributions (activation energies of MFF model range from 190 kJ/mol to 250 kJ/mol, activation energies of SFF model range from 220 kJ/mol to 240 kJ/mol), which indicates a homogeneous chemical bond structure of the Type I kerogen. The hydrocarbon generated curves from Type I kerogen were calculated by using the two models with a linear heating rate (3.3 K/Ma). It indicates that the hydrocarbon generation potentials (reaction fractions) are underestimated by using the SFF model during the kerogen thermal degradation for the components with chemical bond of lower and higher activation energies, while this problem can be avoided by using the MFF model. The calculated temperatures for 50% transformation ratio (TR) of all samples differ by as much as 20 °C. For the SFF model, the hydrocarbon generation curve obtained by using the weighted averaged kinetic parameters and the SFF model almost includes every curve calculated by using its own kinetic parameters. While the curve obtained by using the weighted averaged kinetic parameters and the MFF model cannot include every curve for all samples, it lies at the position of the averaged curve of all samples. The application of the MFF model in Songliao Basin shows that if TR 10% is taken as the onset of hydrocarbon generation, the threshold depth of hydrocarbon generation is about 1700 m, which is consistent with other geochemical parameters, such as S₁/TOC, S₁/(S₁ + S₂) and HC/TOC.     

Thermodynamic Analysis of Heavy Metals Biosorption by Two Macroalgae

The thermodynamic process of two macroalgae, Sargassum fusiforme and Lamin aria japonica, absorbing heavy, metal ions Cu^2 , Pb^2 , Cd^2 and Ni^2 . has been studied. The result indicates that the absorption isotherms of these two macroalgae clearly accord with the Landmuir adsorption model. The absorptive processes of S. fusiforme and L. japonica for Cu^2 are endothermal, and at 35℃, the adsorption heat of these two algae is 59.5kJ/mol and 76.8 kJ/mol respectively. Temperature could affect the algae‘s adsorption capacity. Their adsorption capacity increases with temperature (25℃ and 35℃).     

MECHANISM OF URANIUM ADSORPTION ON AMIDOXIME RESIN

The mechanism of uranium adsorption from seawater by polyacrylamidoxime resin is investigated by means of the experiments of adsorption isotherm and adsorption rate. The uranium uptake increases with the adsorption temperature and varies with the pH of seawater. Thermochemical and kinetic calculation show that the enthalpy change (△H) and the activation energy (E) of the uranium adsorption are 42.4 42.4 kJ mol-1 and 41.2 kJ mol-1 respectively, indicating that the uranium adsorption on the resin proceeds via a certain complex chemical reaction in which the amidoxime group in the resin chelates uranyl ions.     

Effects of composition and pore structure on the reservoir gas capacity of Carboniferous shale from Qaidam Basin,China

Shale adsorption and breakthrough pressure are important indicators of shale gas development and key factors in evaluating the reservoir capacities of shales. In this study, geochemical tests, pore-structure tests, methane adsorption tests, and breakthrough-pressure tests were conducted on shales from the Carboniferous Hurleg Formation in eastern Qaidam Basin. The effects of the shale compositions and pore structures on the adsorption and breakthrough pressures were studied, and the reservoir capacities of the shales were evaluated by analyzing the shale adsorptions and sealing effects. The results indicate that the organic carbon content was only one of factors in affecting the adsorption capacity of the shale samples while the effect of the clay minerals was limited. Based on the positive correlation between the adsorption capacity and specific surface area of the shale, the specific surface area of the micropores can be used as an indicator to determine the adsorption capacity of shale. The micro-fracturing of brittle minerals, such as quartz, create a primary path for shale gas breakthrough, whereas the expansion of clay minerals with water greatly increases the breakthrough pressure in the shale samples. Methane adsorption tests showed that maximum methane adsorption for shale samples Z045 and S039 WAS 0.107 and 0.09655 mmol/g, respectively. The breakthrough pressure was 39.36 MPa for sample S039, maintained for 13 days throughout the experiment; however, no breakthrough was observed in sample Z045 when subjected to an injected pressure of 40 MPa for 26 days. This indicates that sample Z045, corresponding to a depth of 846.24 m, exhibited higher adsorption capacity and a better reservoir-sealing effect than sample S039 (498.4 m depth). This study provides useful information for future studies of Qaidam Basin shale gas exploration and development and for evaluation of shale quality.     

滨海砂土对可溶性油的吸附作用和影响因素研究

在现场自然地理、水文地质条件调查的基础上,对青岛海水浴场采集砂和海水样品进行主要物理化学性质分析,探讨吸附机理的影响因素,通过吸附试验建立砂样对可溶性油吸附的动力学方程和吸附等温线,经过批量试验确定温度、盐度和pH值对吸附量的影响。研究结果表明,砂土对可溶性油吸附的平衡吸附量为90~110 mg/kg,吸附平衡时间为14~16 h,符合Henry型直线等温物理吸附。对等温式进一步分析发现,当水相中可溶性油浓度低于一定数值时,不但不产生吸附,反而会使污染沙滩上的残留油分释放出来,造成二次污染。     

Adsorption Behavior of Cr(VI) on Al-Fe Cointercalated Bentonite

An efficient Al-Fe cointercalated bentonite composite material (Al-Fe/Bent) which is capable of removing hexavalent chromium [Cr(VI)] from aqueous solutions was prepared. The batch experiment studies were conducted to evaluate the adsorption performance of Cr(VI) contained in aqueous solution. The XRD results showed the spacing of layers of bentonite was increased due to the aluminum and iron polycation intercalated into the layer of bentonite. The removal rate of Cr(VI) from the aqueous solution could be up 87.4% under the condition of the dosage of Al-Fe/Bent 8 g/L, pH 4, and a contact time of 60 min. The equilibrium data fitted well to the Freundlich model. The adsorption process could be well described by the pseudosecond order kinetic model.     

壳聚糖/纳米铜复合微球的制备及其对刚果红染料的脱色性能

以壳聚糖和CuCl₂·2H₂O为原料,分别采用直接负载法和吸附法成功制备了壳聚糖/纳米铜复合微球,运用傅里叶变换红外光谱(FT-IR)、X-射线衍射(XDR)和扫描电镜(SEM)对催化剂结构进行了表征。以刚果红(CR)染料为目标污染物,评价了催化剂的制备方法、制备条件及氢转移催化反应条件对其催化性能的影响。结果表明,由直接负载法(CS/CuNPs)和吸附法(CS/CuNPs-X)制备的壳聚糖/纳米铜复合微球在CR染料浓度为100 mg/L,催化剂投加量为0.05 g,供氢体浓度为0.05 mol/L的氢转移催化反应条件下,催化反应进行180和60 min时CR脱色率可分别达95.8%和96.8%。CS/CuNPs-X比CS/CuNPs表现了更高的对CR氢转移催化反应的催化速率。两种催化剂催化还原CR染料的反应均符合准一级动力学模型。在连续循环使用10次后,CS/CuNPs和CS/CuNPs-X对CR的脱色率分别为93.9%和89.4%,表明催化剂具有良好的重复使用性能。     

基于BP神经网络的天然气水合物相平衡计算及预测

针对天然气水合物相平衡问题,文中提出用基于带动量因子的BP神经网络进行计算和预测。首先用遗传算法优化确定BP神经网络的结构和参数,得到最优化结构的神经网络;其次结合Levenberg-Marquart优化算法,建立天然气水合物相平衡计算及预测的神经网络模型;最后以实验测定的(CH4 CO2 H2S)三元酸性天然气水合物体系的平衡数据为训练和预测样本进行了计算。计算表明,预测结果与实验数据有良好的一致性,而且由于BP神经网络作为所谓的“纯粹”的算法不需要热力学模型,这对于相平衡计算是非常方便的,所以是研究天然气水合物相平衡计算及预测的一种新的有效方法。     

北太平洋和北冰洋大气中多氯联苯的浓度与气固分配行为

Polychlorinated biphenyls(PCBs) were measured in atmospheric samples collected from the North Pacific to the Arctic Ocean between July and September 2012 to study the atmospheric concentration characteristics of PCBs and their gas/particle partitioning. The mean concentration of 26 ∑PCBs(vapor plus particulate phase)(∑PCBs) was 19.116 pg/m3 with a standard deviation of 13.833 pg/m3. Three most abundant congeners were CB-28,-52 and-77, accounting for 43.0% to ∑PCBs. The predominance of vapor PCBs(79.0% to ∑PCBs) in the atmosphere was observed. PCBs were negative correlated with the latitudes and inverse of the absolute temperature(1/T). The significant correlation for most congeners was also observed between the logarithm of gas/particle partition coefficient(log KP) and 1/T. Shallower slopes(from-0.15 to-0.46, average-0.27) were measured from the regression of the logarithm of sub-cooled liquid vapor pressures(logpo L) and log KP for all samples. The difference of the slopes and intercepts among samples was insignificant(p0.1), implying adsorption and/or absorption processes and the aerosol composition did not differ significantly among different samples. By comparing three models, the J-P adsorption model, the octanol/air partition coefficient(KOA) based model and the soot-air model, the gas/particle partitioning of PCBs in the Arctic atmosphere was simulated more precisely by the soot-air model, and the adsorption onto elemental carbon is more sensitive than the absorption into organic matters of aerosols, especially for lowchlorinated PCB congeners.     

固定化海藻对金属离子吸附效果的研究

研究了固定化海带吸附含铜、镉溶液的过程,结果表明:非活性海带吸附水溶液中铜、镉离子的动力学过程可以用班厄姆吸附速率方程描述,铜和镉的吸附速率常数分别为0.1078和0.03028min-1;生物吸附过程符合Langmuir模型,根据Langmuir吸附等温模型的计算结果,得到固定化海带对铜和镉离子的最大吸附量分别为83.3和112.4mg/g,海带对铜离子的亲和性比对镉离子强.