response surface model

  • 文章类型: Journal Article
    为了延长钛合金产品的使用寿命,有必要改进抛光方法,以减少工件表面的残留缺陷。本文采用Halbach阵列辅助的钛合金磁性磨粒抛光方法。首先对磁场强度的分布进行了模拟和验证,以了解本工作中使用的Halbach阵列的特性。然后,通过进行抛光试验,研究了抛光工具的抛光性能,旨在显示剪切力与表面粗糙度随抛光时间的关系,并对抛光过程中的表面形貌进行了分析。响应面模型建立后,对最佳抛光参数进行了研究,以获得最大剪切力和最小表面粗糙度的合适参数。结果表明,可以达到最大剪切力6.11N和最小表面粗糙度Sa88nm,分别,在(1)抛光工具速度为724.254r·min-1,工作间隙为0.5mm的条件下,磨料粒度为200μm;(2)抛光工具速度为897.87r·min-1,工作间隙为0.52mm,和160μm的磨料粒度。
    To extend the working life of products made of titanium alloy, it is necessary to improve the polishing method to diminish the remaining defects on the workpiece surface. The Halbach array-assisted magnetic abrasive particle polishing method for titanium alloy was employed in this work. The distribution of magnetic field strength was simulated and verified at first to learn the characteristics of the Halbach array used in this work. Then, the polishing performance of the polishing tool was studied by conducting the polishing test, which aimed to display the relationship between shear force and surface roughness with polishing time, and the surface morphology during polishing was also analyzed. Following the establishment of the response surface model, a study on the optimal polishing parameters was conducted to obtain the suitable parameters for maximum shear force and minimum surface roughness. The results show that the maximum shear force 6.11 N and minimum surface roughness Sa 88 nm can be attained, respectively, under the conditions of (1) polishing tool speed of 724.254 r·min-1, working gap of 0.5 mm, and abrasive particle size of 200 μm; and (2) polishing tool speed of 897.87 r·min-1, working gap of 0.52 mm, and abrasive particle size of 160 μm.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    β-内酰胺类抗生素,在世界范围内广泛使用,由于它们在环境中的积累,对人类健康和生态安全构成重大风险。最近的研究已经证明了过渡金属活化亚硫酸盐系统的功效,如Fe(Ⅲ)/HSO3-,从水中去除PPCPs。然而,关于它们降解β-内酰胺类抗生素的能力的研究仍然很少。本文评价了14种β-内酰胺类抗生素在Fe(Ⅲ)/HSO3-体系中的降解情况,并利用MLR方法建立了分子描述符与降解速率相关的QSAR模型。以头孢唑啉为例,这项研究通过NPA电荷和福井功能分析预测降解途径,UPLC-MS产品分析证实。调查进一步探讨了HSO3-剂量等变量的影响,底物浓度,Fe(Ⅲ)用量,初始pH值和常见的水基质的存在,包括腐殖酸和碳酸氢盐对降解效率的影响。确定头孢唑啉在Fe(Ⅲ)/HSO3-体系中降解的最佳条件为93.3μMHSO3-,8.12μMFe(Ⅲ)和3.61的初始pH值,在此条件下,Fe(Ⅲ)的用量与初始pH值的相互作用显着影响降解效率。本研究不仅为β-内酰胺类抗生素的降解提供了新的途径,而且拓展了Fe(Ⅲ)/HSO3-体系的理论应用范围。
    β-lactam antibiotics, extensively used worldwide, pose significant risks to human health and ecological safety due to their accumulation in the environment. Recent studies have demonstrated the efficacy of transition metal-activated sulfite systems, like Fe(Ⅲ)/HSO3-, in removing PPCPs from water. However, research on their capability to degrade β-lactam antibiotics remains sparse. This paper evaluates the degradation of 14 types of β-lactam antibiotics in Fe(Ⅲ)/HSO3- system and establishes a QSAR model correlating molecular descriptors with degradation rates using the MLR method. Using cefazolin as a case study, this research predicts degradation pathways through NPA charge and Fukui function analysis, corroborated by UPLC-MS product analysis. The investigation further explores the influence of variables such as HSO3- dosage, substrate concentration, Fe(Ⅲ) dosage, initial pH and the presence of common seen water matrices including humic acid and bicarbonate on the degradation efficiency. Optimal conditions for cefazolin degradation in Fe(Ⅲ)/HSO3- system were determined to be 93.3 μM HSO3-, 8.12 μM Fe(Ⅲ) and an initial pH of 3.61, under which the interaction of Fe(Ⅲ) dosage with initial pH was found to significantly affect the degradation efficiency. This study not only provides a novel degradation approach for β-lactam antibiotics but also expands the theoretical application horizon of the Fe(Ⅲ)/HSO3- system.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    壳聚糖,从几丁质中获得的生物聚合物,以其对染料的卓越吸附能力而闻名,毒品,和脂肪,以及其多样化的抗菌特性。本研究探索了从鸡毒菌丝体中提取壳聚糖并进行表征。水分含量,灰分含量,水结合能力,脂肪结合能力,并测定了提取的壳聚糖的脱乙酰度。壳聚糖具有70%的高收率,结晶度为49.07%,86%的脱乙酰度,和有效的抗革兰氏阴性和革兰氏阳性细菌的抗菌性能。该研究还通过分析pH等特定因素来检查壳聚糖去除亚甲基蓝(MB)染料的吸附能力,反应时间,和MB浓度使用响应面模型。在pH为6,反应时间约为60分钟和初始染料浓度为16ppm时,MB染料的最高去除率为91.6%。本实验设计可应用于壳聚糖对染料等其他有机化合物的吸附,蛋白质,毒品,和脂肪。
    Chitosan, a biopolymer obtained from chitin, is known for its remarkable adsorption abilities for dyes, drugs, and fats, and its diverse array of antibacterial characteristics. This study explores the extraction and characterization of chitosan from the mycelium of Amanita phalloides. The moisture content, ash content, water binding capacity, fat binding capacity, and degree of deacetylation of the extracted chitosan were determined. The chitosan exhibited a high yield of 70%, crystallinity of 49.07%, a degree of deacetylation of 86%, and potent antimicrobial properties against both Gram-negative and Gram-positive bacteria. The study also examined the adsorption capabilities of chitosan to remove methylene blue (MB) dye by analysing specific factors like pH, reaction time, and MB concentration using the response surface model. The highest degree of MB dye removal was 91.6% at a pH of 6, a reaction time of around 60 min and an initial dye concentration of 16 ppm. This experimental design can be applied for chitosan adsorption of other organic compounds such as dyes, proteins, drugs, and fats.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    评估装甲钝器创伤(BABT)背后是防止军事人员非穿透性伤害的关键一步,这可能是由于射弹撞击防弹衣的动能转移造成的。尽管当前的NIJStandard-0101.06标准侧重于防止装甲背面过度变形,本标准不考虑撞击位置的可变性,胸部器官和组织材料特性,和损伤阈值,以评估潜在的伤害。为了解决这个差距,通过从幸存者数据库中重新创建特定案例并生成伤害风险曲线,已采用有限元(FE)人体模型(HBM)来研究BABT撞击条件的变异性。然而,这些确定性分析主要使用代表男性第50百分位数的模型,不调查系统内固有的不确定性和可变性,从而限制了在不同军事人群中调查伤害风险的普遍性。国防部资助的I-PREDICT未来海军能力(FNC)引入了概率HBM,它考虑了组织材料和失效特性的不确定性和可变性,人体测量学,和外部加载条件。本研究利用I-PREDICTHBM对三个胸部撞击位置-肝脏进行BABT模拟,心,和下腹部。对BABT事件引起的组织水平应变的概率分析用于确定实现器官水平损伤的军事战斗失能量表(MCIS)的概率,并采用新损伤严重程度评分(NISS)进行全身损伤风险评估。器官水平的MCIS指标显示,对心脏的影响会对心脏和脾脏造成严重伤害,而对肝脏的影响会导致肋骨骨折和肝脏严重撕裂。下腹部的撞击会导致脾脏撕裂。仿真结果表明,在当前的保护标准下,根据撞击位置,全身受伤的风险在6%到98%之间变化,对心脏的影响最严重,然后是肝脏和下腹部的撞击。这些结果表明,当前的防弹衣保护标准可能会导致特定位置的严重伤害,但其他人没有受伤。
    Evaluating Behind Armor Blunt Trauma (BABT) is a critical step in preventing non-penetrating injuries in military personnel, which can result from the transfer of kinetic energy from projectiles impacting body armor. While the current NIJ Standard-0101.06 standard focuses on preventing excessive armor backface deformation, this standard does not account for the variability in impact location, thorax organ and tissue material properties, and injury thresholds in order to assess potential injury. To address this gap, Finite Element (FE) human body models (HBMs) have been employed to investigate variability in BABT impact conditions by recreating specific cases from survivor databases and generating injury risk curves. However, these deterministic analyses predominantly use models representing the 50th percentile male and do not investigate the uncertainty and variability inherent within the system, thus limiting the generalizability of investigating injury risk over a diverse military population. The DoD-funded I-PREDICT Future Naval Capability (FNC) introduces a probabilistic HBM, which considers uncertainty and variability in tissue material and failure properties, anthropometry, and external loading conditions. This study utilizes the I-PREDICT HBM for BABT simulations for three thoracic impact locations-liver, heart, and lower abdomen. A probabilistic analysis of tissue-level strains resulting from a BABT event is used to determine the probability of achieving a Military Combat Incapacitation Scale (MCIS) for organ-level injuries and the New Injury Severity Score (NISS) is employed for whole-body injury risk evaluations. Organ-level MCIS metrics show that impact at the heart can cause severe injuries to the heart and spleen, whereas impact to the liver can cause rib fractures and major lacerations in the liver. Impact at the lower abdomen can cause lacerations in the spleen. Simulation results indicate that, under current protection standards, the whole-body risk of injury varies between 6 and 98% based on impact location, with the impact at the heart being the most severe, followed by impact at the liver and the lower abdomen. These results suggest that the current body armor protection standards might result in severe injuries in specific locations, but no injuries in others.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    葡萄果渣是从葡萄酒生产中获得的主要副产品,仍然富含生物活性化合物。在通过可持续方法进行废物/副产品再利用的框架内,在这项工作中,使用了各种绿色方法从“Sangiovese”葡萄酿酒产生的果渣中回收花青素。超声和微波辅助提取(UAE和MAE)与绿色溶剂的使用相结合,如酸化水,乙醇/水混合物,和天然深共晶溶剂(NaDES),并将其功效与基于甲醇/酸化水混合物的常规方法进行了比较。阿联酋的总花色苷指数范围为36.9至75.2mg/gDW,MAE的DW从54.4到99.6mg/g,而常规提取的DW为47.1mg/g。将实验设计(DoE)方法应用于MAE,最有效的技术。温度,时间,固液比设置为X变量,而malvidin-3-O-葡萄糖苷含量和抗氧化活性被用作响应变量,通过高效液相色谱-二极管阵列检测(HPLC-DAD)和2,2-二苯基-1-吡啶酰肼(DPPH)测定,分别。温度和时间与提取物的抗氧化活性呈正相关,而当考虑malvidin-3-O-葡糖苷浓度作为响应变量时,发现为阴性。因此,温度的最佳条件,时间和固液比根据所选择的变量而不同.结果强调了使用响应面方法时选择准确响应的重要性。
    Grape pomace is the main by-product obtained from wine production that is still enriched in bioactive compounds. Within a framework of waste/by-product reuse through a sustainable approach, various green methods were utilized in this work to recover anthocyanins from the pomace resulting from \"Sangiovese\" grape vinification. Ultrasound- and Microwave-Assisted Extractions (UAE and MAE) were coupled with the use of green solvents, such as acidified water, an ethanol/water mixture, and Natural Deep Eutectic Solvents (NaDES), and their efficacy was compared with that of a conventional method based on a methanol/acidified water mixture. The Total Anthocyanin Index ranged from 36.9 to 75.2 mg/g DW for UAE, and from 54.4 to 99.6 mg/g DW for MAE, while resulting in 47.1 mg/g DW for conventional extraction. A Design of Experiments (DoE) approach was applied to MAE, the most efficient technique. Temperature, time, and the solid-to-liquid ratio were set as X variables, while malvidin-3-O-glucoside content and antioxidant activity were used as response variables, measured by High-Performance Liquid Chromatography with Diode Array Detection (HPLC-DAD) and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay, respectively. The correlation between temperature and time and the antioxidant activity of the extract was positive, while it was found to be negative when considering malvidin-3-O-glucoside concentration as a response variable. Thus, the optimal conditions in temperature, time and solid-to-liquid ratio were different depending on the chosen variable. The results underline the importance of selecting an accurate response when using the response surface methodology approach.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    我国O3污染水平不断上升,显著加剧了O3对健康的长期危害,并且需要针对NOx和VOCs减排的优化健康导向策略。这里,通过合并O3相关死亡率的响应面模型和优化模块,我们开发了O3控制策略的集成评估和优化系统。将该系统应用于长江三角洲(YRD),我们评估了2013年至2017年死亡率变化的驱动因素,量化的时空O3相关死亡率对前体减排的反应,并优化了以健康为导向的控制策略。结果表明,从2013年到2017年,NOx排放减少不足加上VOCs控制不足加剧了与O3相关的死亡率,尤其是在春季和秋季。由于较高的VOC限制特性,北方YRD应促进VOCs控制,而在YRD南部,减少NOx排放更为有利。此外,与无季节差异的控制策略相比,在春季和夏季后期促进NOx减排并在春季和秋季促进VOCs控制可进一步将O3相关死亡率降低近10%。这些发现强调,在空间和时间上区分的NOx和VOCs排放控制策略可以获得更多与O3相关的健康益处,为世界各地臭氧污染严重的地区提供有价值的见解。
    The increasing level of O3 pollution in China significantly exacerbates the long-term O3 health damage, and an optimized health-oriented strategy for NOx and VOCs emission abatement is needed. Here, we developed an integrated evaluation and optimization system for the O3 control strategy by merging a response surface model for the O3-related mortality and an optimization module. Applying this system to the Yangtze River Delta (YRD), we evaluated driving factors for mortality changes from 2013 to 2017, quantified spatial and temporal O3-related mortality responses to precursor emission abatement, and optimized a health-oriented control strategy. Results indicate that insufficient NOx emission abatement combined with deficient VOCs control from 2013 to 2017 aggravated O3-related mortality, particularly during spring and autumn. Northern YRD should promote VOCs control due to higher VOC-limited characteristics, whereas fastening NOx emission abatement is more favorable in southern YRD. Moreover, promotion of NOx mitigation in late spring and summer and facilitating VOCs control in spring and autumn could further reduce O3-related mortality by nearly 10% compared to the control strategy without seasonal differences. These findings highlight that a spatially and temporally differentiated NOx and VOCs emission control strategy could gain more O3-related health benefits, offering valuable insights to regions with severe ozone pollution all over the world.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Meta-Analysis
    由于微生物的耐热性增强和食品基质的低热导率,低水分食品中的微生物热灭活具有挑战性。在这项研究中,我们利用了先前关于这个主题的工作来模拟确定低水分食品中微生物热失活的关键实验特征。我们确定了27项研究,其中包含782个平均D值,并开发了线性混合效应模型来评估微生物类型的影响,矩阵结构和组成,水活动,温度,以及接种和恢复方法对细胞死亡动力学的影响。线性混合效应模型的组内相关统计量(I2)和条件R2值分别为:大肠杆菌(R2-0.91,I2-83%),真菌(R2-0.88,I2-85%),L.单核细胞增多症(R2-0.84,I2-75%),沙门氏菌(R2-0.69,I2-46%)。最后,建立了全局响应面模型(RSM),以进一步研究aw和温度对失活的非线性影响。这些模型的拟合程度因R20.88(E.大肠杆菌)到0.35(真菌)。进一步将沙门氏菌数据划分为基于基质结构的单个RSM模型,改进模型拟合R2为0.90(糊状产品)和0.48(粉末状产品)。这表明数据多样性与模型性能之间存在负相关关系。
    Microbial thermal inactivation in low moisture foods is challenging due to enhanced thermal resistance of microbes and low thermal conductivity of food matrices. In this study, we leveraged the body of previous work on this topic to model key experimental features that determine microbial thermal inactivation in low moisture foods. We identified 27 studies which contained 782 mean D-values and developed linear mixed-effect models to assess the effect of microorganism type, matrix structure and composition, water activity, temperature, and inoculation and recovery methods on cell death kinetics. Intraclass correlation statistics (I2) and conditional R2 values of the linear mixed effects models were: E. coli (R2-0.91, I2-83%), fungi (R2-0.88, I2-85%), L. monocytogenes (R2-0.84, I2-75%), Salmonella (R2-0.69, I2-46%). Finally, global response surface models (RSM) were developed to further study the non-linear effect of aw and temperature on inactivation. The fit of these models varied by organisms from R2 0.88 (E. coli) to 0.35 (fungi). Further dividing the Salmonella data into individual RSM models based on matrix structure improved model fit to R2 0.90 (paste-like products) and 0.48 (powder-like products). This indicates a negative relationship between data diversity and model performance.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    响应面模型(RSM)是现代麻醉的新趋势。RSM在麻醉领域表现出显著的适用性。然而,RSM和logistic回归(LR)在不同手术中的比较分析在当前文献中仍然相对有限。我们假设使用具有响应面模型(RSM)和逻辑回归(LR)的全静脉麻醉(TIVA)技术可以预测接受电视辅助开胸手术(VATS)的患者麻醉的出现。本研究旨在证明LR,像RSM一样,可用于提高患者安全性并实现手术后恢复(ERAS)。这是一个潜在的,观察性研究与数据再分析。纳入了29名患者(美国麻醉医师协会(ASA)II级和III级),他们在TIVA下接受了VATS进行选择性肺或纵隔手术。我们监测了麻醉的出现,并记录了确切的恢复反应时间点(RR)。检查了不同浓度的影响,并将其纳入RSM和LR。Greco和LR模型的受试者工作特征(ROC)曲线面积分别为0.979(置信区间:0.987至0.990)和0.989(置信区间:0.989至0.990),分别。这两个模型在预测恢复反应的概率方面没有显着差异。总之,LR模式有效,可应用于接受VATS或其他类似模式手术的患者.此外,RSM明显更复杂,精度与LR模型相似;然而,LR模型更易于访问。因此,LR模型是一种更简单的工具,可以预测在TIVA联合瑞芬太尼和丙泊酚下接受VATS的患者的觉醒.
    Response surface models (RSMs) are a new trend in modern anesthesia. RSMs have demonstrated significant applicability in the field of anesthesia. However, the comparative analysis between RSMs and logistic regression (LR) in different surgeries remains relatively limited in the current literature. We hypothesized that using a total intravenous anesthesia (TIVA) technique with the response surface model (RSM) and logistic regression (LR) would predict the emergence from anesthesia in patients undergoing video-assisted thoracotomy surgery (VATS). This study aimed to prove that LR, like the RSM, can be used to improve patient safety and achieve enhanced recovery after surgery (ERAS). This was a prospective, observational study with data reanalysis. Twenty-nine patients (American Society of Anesthesiologists (ASA) class II and III) who underwent VATS for elective pulmonary or mediastinal surgery under TIVA were enrolled. We monitored the emergence from anesthesia, and the precise time point of regained response (RR) was noted. The influence of varying concentrations was examined and incorporated into both the RSM and LR. The receiver operating characteristic (ROC) curve area for Greco and LR models was 0.979 (confidence interval: 0.987 to 0.990) and 0.989 (confidence interval: 0.989 to 0.990), respectively. The two models had no significant differences in predicting the probability of regaining response. In conclusion, the LR model was effective and can be applied to patients undergoing VATS or other procedures of similar modalities. Furthermore, the RSM is significantly more sophisticated and has an accuracy similar to that of the LR model; however, the LR model is more accessible. Therefore, the LR model is a simpler tool for predicting arousal in patients undergoing VATS under TIVA with Remifentanil and Propofol.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    通过在从实际市政污水处理厂(MWWTP)收集的实际二级废水中应用太阳能光电Fenton(SPEF)工艺,评估了同时出现的污染物(CEC)去除和野生微生物的灭活。使用20L的四种CEC的混合物作为模型污染物(200μg/L的对乙酰氨基酚,咖啡因,磺胺二甲嘧啶,和磺胺甲恶唑各一种)。SPEF过程是在阳光充足的日子里进行的,在周围中性pH下,使用络合物Fe3+-EDDS,在太阳能电化学-跑道池反应器(SEC-RPR)中。最初,使用基于电流密度的响应面模型确定了CECs降解的最佳条件,铁络合物浓度和Fe3+-EDDS添加时间(允许先前积累H2O2)作为模型输入。24.6mA/cm2的电流密度,0.089mM的Fe3-EDDS复合物浓度和3.8分钟的先前H2O2积累是最终的最佳条件,随后将其应用于同时降解CECs合成混合物和野生微生物灭活在实际的二级流出物中。在30分钟内实现了约85%的CECs去除和完全的大肠杆菌灭活,大约,而粪肠球菌和总大肠杆菌在60分钟和75分钟的检测限下可以灭活,分别。
    Simultaneous contaminants of emerging concern (CECs) removal and wild microorganisms\' inactivation was evaluated by applying solar photoelectro-Fenton (SPEF) process in actual secondary effluent collected from a real municipal wastewater treatment plant (MWWTP). 20 L of a mixture of four CECs was used as model pollutants (200 μg/L of acetaminophen, caffeine, sulfamethazine, and sulfamethoxazole each one). The SPEF process was carried out on fully sunny days, at circumneutral pH using the complex Fe3+-EDDS, in a solar electrochemical - raceway pond reactor (SEC-RPR). Initially, the optimal conditions for CECs degradation were determined using a response surface model based on current density, iron complex concentration and Fe3+-EDDS addition time (to allow previous accumulation of H2O2) as model inputs. A current density of 24.6 mA/cm2, a Fe3+-EDDS complex concentration of 0.089 mM and 3.8 min of previous H2O2 accumulation were the resulting optimum conditions that were afterwards applied for the simultaneous degradation of the CECs synthetic mixture and wild microorganisms inactivation in actual secondary effluent. About 85% CECs removal and complete E. coli inactivation were achieved in 30 min, approximately, while E. faecalis and total coliforms could be inactivated under detection limit in 60 min and 75 min, respectively.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    具有所需阳离子度和分子量的阳离子聚丙烯酰胺(CPAMs)的合成对于各种行业至关重要,包括废水处理,采矿,paper,化妆品化学,和其他人。先前的研究已经证明了优化合成条件以获得高分子量CPAM乳液的方法以及阳离子度对絮凝过程的影响。然而,尚未讨论优化输入参数以获得具有所需阳离子度的CPAMs。传统的优化方法在现场生产CPAM时耗时且成本高,因为CPAM合成的输入参数是使用单因素实验进行优化的。在这项研究中,我们利用响应面法来优化合成条件,特别是单体浓度,阳离子单体的含量,以及发起人的内容,以获得具有所需阳离子度的CPAM。这种方法克服了传统优化方法的缺点。我们成功合成了三种阳离子度范围广泛的CPAM乳液:低(21.85%),中等(40.25%),和高(71.17%)水平的阳离子度。这些CPAM的优化条件如下:单体浓度为25%,单体阳离子含量为22.5%,44.41%,和77.61%,分别,引发剂含量为0.475%,0.48%,和0.59%,分别。所开发的模型可用于快速优化合成具有不同阳离子度的CPAM乳液的条件,以满足废水处理应用的需求。合成的CPAM产品在废水处理中有效地进行,处理后的废水符合技术调节参数。1H-NMR,FTIR,SEM,BET,动态光散射,和凝胶渗透色谱用于确认聚合物的结构和表面。
    The synthesis of cationic polyacrylamides (CPAMs) with the desired cationic degree and molecular weight is essential for various industries, including wastewater treatment, mining, paper, cosmetic chemistry, and others. Previous studies have already demonstrated methods to optimize synthesis conditions to obtain high-molecular-weight CPAM emulsions and the effects of cationic degrees on flocculation processes. However, the optimization of input parameters to obtain CPAMs with the desired cationic degrees has not been discussed. Traditional optimization methods are time-consuming and costly when it comes to on-site CPAM production because the input parameters of CPAM synthesis are optimized using single-factor experiments. In this study, we utilized the response surface methodology to optimize the synthesis conditions, specifically the monomer concentration, the content of the cationic monomer, and the content of the initiator, to obtain CPAMs with the desired cationic degrees. This approach overcomes the drawbacks of traditional optimization methods. We successfully synthesized three CPAM emulsions with a wide range of cationic degrees: low (21.85%), medium (40.25%), and high (71.17%) levels of cationic degree. The optimized conditions for these CPAMs were as follows: monomer concentration of 25%, content of monomer cation of 22.5%, 44.41%, and 77.61%, respectively, and initiator content of 0.475%, 0.48%, and 0.59%, respectively. The developed models can be utilized to quickly optimize conditions for synthesizing CPAM emulsions with different cationic degrees to meet the demands of wastewater treatment applications. The synthesized CPAM products performed effectively in wastewater treatment, with the treated wastewater meeting the technical regulation parameters. 1H-NMR, FTIR, SEM, BET, dynamic light scattering, and gel permeation chromatography were employed to confirm the structure and surface of the polymers.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

公众号