2-Propanol

2 - 丙醇
  • 文章类型: Journal Article
    木质素,一种重要的可再生生物聚合物,作为地球芳烃和碳的主要来源。它的解聚为生产酚类精细化学品提供了巨大的潜力。这项研究评估了促进的镍基双金属催化剂(Ni-Co/C和Ni-Cu/C)负载在异丙醇中的活性炭上用于木质素解聚,与单金属同行相比。BET,SEM,EDX,和XPS分析突出了它们的物理化学性质和促销效果,增强氢解活性和氢转化。反应参数探索阐明了对木质素解聚的影响,以钴和铜为促进剂,显着提高转化率和单体收率。Ni-Co/C在特定条件下表现出最高的木质素转化率(94.2%)和最大的单体产率(53.1wt%),与Ni/C相比,活化能更低(36.1kJ/mol)和更高的周转频率(31.6h-1)。FT-IR,GPC,GC-FID,和GC-MS分析证实有效的解聚,鉴定20种单体产品。提出的反应机理强调了镍基双金属催化剂用于木质素增值的潜力,为开发有效的木质素氢解催化系统提供见解。这项研究增进了人们的理解,并促进了木质素加价的选择性催化工艺的开发。
    Lignin, a vital renewable biopolymer, serves as the Earth\'s primary source of aromatics and carbon. Its depolymerization presents significant potential for producing phenolic fine chemicals. This study assesses promoted Ni-based bimetallic catalysts (Ni-Co/C and Ni-Cu/C) supported on activated carbon in isopropanol for lignin depolymerization, compared to monometallic counterparts. BET, SEM, EDX, and XPS analyses highlight their physicochemical properties and promotional effects, enhancing hydrogenolysis activity and hydrogen transformation. Reaction parameter exploration elucidates the influence on lignin depolymerization, with cobalt and copper as promoters notably increasing conversion and monomer yield. Ni-Co/C exhibits the highest lignin conversion (94.2%) and maximum monomer yield (53.1 wt%) under specified conditions, with lower activation energy (36.1 kJ/mol) and higher turnover frequency (31.6 h-1) compared to Ni/C. FT-IR, GPC, GC-FID, and GC-MS analyses confirm effective depolymerization, identifying 20 monomer products. Proposed reaction mechanisms underscore the potential of Ni-based bimetallic catalysts for lignin valorization, offering insights into developing efficient catalytic systems for lignin hydrogenolysis. This research enhances understanding and facilitates the development of selective catalytic processes for lignin valorization.
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  • 文章类型: Journal Article
    用于有机溶剂脱水的膜基渗透汽化(PV)在化工和石化行业中具有重要意义。在这项工作中,高铝ZSM-5沸石膜是通过氟化物辅助的二次生长在α-氧化铝管状载体上合成的,使用丝光沸石骨架倒置(MFI)纳米种子(〜110nm)和无模板的低Si/Al合成溶液比例为10。通过XRD表征,EDX,和SEM显示,制备的膜为纯相ZSM-5沸石膜,Si/Al比为3.8,厚度为2.8μm。随后,两类光伏性能参数(即,通量与分离因子和渗透与选择性)用于系统地检查操作条件对不同有机溶剂(甲醇,乙醇,正丙醇,和异丙醇),并探讨了它们的PV机理。利用渗透性和选择性有效地解决了操作条件对光伏性能的影响,从而阐明了膜对分离性能的内在贡献。结果表明,有机溶剂PV脱水过程中的传质主要由吸附-扩散机制主导。此外,高极性水和甲醇分子在膜孔内的扩散具有很强的相互减缓作用,导致渗透率明显低于其他二元系统。然而,水/低极性有机溶剂的传质过程(乙醇,正丙醇,和异丙醇)混合物主要受亲和力差异引起的竞争性吸附控制。此外,高铝ZSM-5沸石膜对水/异丙醇混合物具有优异的PV脱水性能。
    Membrane-based pervaporation (PV) for organic solvent dehydration is of great significance in the chemical and petrochemical industries. In this work, high-aluminum ZSM-5 zeolite membranes were synthesized by a fluoride-assisted secondary growth on α-alumina tubular supports using mordenite framework inverted (MFI) nanoseeds (~110 nm) and a template-free synthesis solution with a low Si/Al ratio of 10. Characterization by XRD, EDX, and SEM revealed that the prepared membrane was a pure-phase ZSM-5 zeolite membrane with a Si/Al ratio of 3.8 and a thickness of 2.8 µm. Subsequently, two categories of PV performance parameters (i.e., flux versus separation factor and permeance versus selectivity) were used to systematically examine the effects of operating conditions on the PV dehydration performance of different organic solvents (methanol, ethanol, n-propanol, and isopropanol), and their PV mechanisms were explored. Employing permeance and selectivity effectively disentangles the influence of operating conditions on PV performance, thereby elucidating the inherent contribution of membranes to separation performance. The results show that the mass transfer during PV dehydration of organic solvents was mainly dominated by the adsorption-diffusion mechanism. Furthermore, the diffusion of highly polar water and methanol molecules within membrane pores had a strong mutual slowing-down effect, resulting in significantly lower permeance than other binary systems. However, the mass transfer process for water/low-polar organic solvent (ethanol, n-propanol, and isopropanol) mixtures was mainly controlled by competitive adsorption caused by affinity differences. In addition, the high-aluminum ZSM-5 zeolite membrane exhibited superior PV dehydration performance for water/isopropanol mixtures.
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  • 文章类型: Journal Article
    背景:酒精中毒是一个重要的全球性问题,已成为一种流行病。因此,确定酒精类型至关重要,因为它可能会影响治疗过程;但是,除乙醇外,没有针对酒精类型的常规实验室诊断方法。在这项研究中,我们的目的是通过结合呼吸测醉器和分光光度法测定的血清乙醇结果来定义一种简单的酒精类型区分方法。
    方法:使用呼吸测醉器和分光光度法测量四种不同类型的酒精:乙醇,异丙醇,甲醇,和乙二醇。进行血清酒精分析,创建了四个血清池,每种都含有不同类型的酒精。使用分光光度法和酶促乙醇测试试剂盒分析池。使用浸渍棉和气球进行了一项实验,以测量不同类型的酒精,模拟酒精测试。基于测量创建算法。
    结果:根据结果,如果呼吸测醉器测试表明读数为阳性且血液乙醇测量为阴性,则消耗的物质可能是甲醇或异丙醇。如果呼吸测醉器和血液测量结果都是阴性,该物质可能是乙二醇。
    结论:这种简单的方法可以确定甲醇或异丙醇的摄入量。这种简单而创新的方法可以帮助不同领域的医疗保健专业人员诊断酒精中毒,更确切地说,有助于降低相关的发病率和死亡率。
    BACKGROUND: Alcohol poisoning is a significant global problem that has become an epidemic. The determination of the alcohol type is hereby essential as it may affect the course of the treatment; however, there is no routine laboratory diagnostic method for alcohol types other than for ethanol. In this study, we aimed to define a simple method for alcohol type differentiation by utilizing a combination of breathalyzer and spectrophotometrically measured serum ethanol results.
    METHODS: A breathalyzer and spectrophotometry were used to measure four different types of alcohol: ethanol, isopropanol, methanol, and ethylene glycol. To conduct serum alcohol analysis, four serum pools were created, each containing a different type of alcohol. The pools were analyzed using the spectrophotometric method with an enzymatic ethanol test kit. An experiment was conducted to measure the different types of alcohol using impreg-nated cotton and a balloon, simulating a breathalyzer test. An algorithm was created based on the measurements.
    RESULTS: Based on the results, the substance consumed could be methanol or isopropanol if the breathalyzer test indicates a positive reading and if the blood ethanol measurement is negative. If both the breathalyzer and the blood measurements are negative, the substance in question may be ethylene glycol.
    CONCLUSIONS: This simple method may determine methanol or isopropanol intake. This straightforward and innovative approach could assist healthcare professionals in different fields with diagnosing alcohol intoxication and, more precisely, help reducing related morbidity and mortality.
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  • 文章类型: Journal Article
    目标:这项研究评估了氯己定(CHX)和异丙醇(IA)对纤维桩与牙本质的即时和后期推出粘结强度(PBS)的影响。材料和方法:在这项体外研究中,对54颗单管前磨牙进行了牙髓治疗,并随机分配到3组(N=18),用蒸馏水(对照组)处理牙本质,2%CHX,和70%的IA后空间准备。纤维桩用TheraCem自粘水泥粘合,并将每组细分为两个亚组(N=9),用于键合后立即进行PBS测量,并且在5000个热循环(5-55°C)之后。然后将根部切开,并测量了他们的PBS。在立体显微镜下以X40放大倍数评估失效模式。数据采用重复测量方差分析和Tukey检验(α=0.05)。结果:24小时后IA组PBS最高(21.12MPa),热循环后最低的PBS属于对照组(7.48MPa)。对照组即刻和后热循环PBS显著低于CHX组(P<0.05)。对照组和CHX组的PBS均低于IA组(P<0.001)。不管是哪种类型的洗涤剂,热循环后观察到PBS的显着减少(P<0.003)。在所有组中,PBS从宫颈向顶端区域显着降低(P<0.001)。结论:根据研究结果,自粘水泥前IA的应用有效地改善了即刻和后期PBS,并且明显比CHX更有效。
    Objectives: This study assessed the effect of chlorhexidine (CHX) and isopropyl alcohol (IA) on immediate and late pushout bond strength (PBS) of fiber posts to dentin. Materials and Methods: In this in vitro study, 54 single-canal premolars were endodontically treated, and randomly assigned to 3 groups (N=18) for root dentin conditioning with distilled water (control), 2% CHX, and 70% IA after post space preparation. Fiber posts were cemented with TheraCem self-adhesive cement, and each group was subdivided into two subgroups (N=9) for PBS measurement immediately after bonding, and after 5000 thermal cycles (5-55°C). The roots were then sectioned, and their PBS was measured. The mode of failure was evaluated under a stereomicroscope at ×40 magnification. Data were analyzed by repeated measures ANOVA and Tukey\'s test (alpha=0.05). Results: The highest PBS was noted in the IA group (21.12 MPa) after 24 hours and the lowest PBS belonged to the control group after thermocycling (7.48 MPa). The immediate and post-thermocycling PBS were significantly lower in the control group than the CHX group (P<0.05). The PBS in both the control and CHX groups was lower than that in the IA group (P<0.001). Regardless of the type of detergent, a significant reduction in PBS was observed after thermocycling (P<0.003). The PBS significantly decreased from the cervical towards the apical region in all groups (P<0.001). Conclusion: According to the results, application of IA before the self-adhesive cement effectively improved the immediate and late PBS, and was significantly more effective than CHX.
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  • 文章类型: Journal Article
    丙酮丁醇梭菌的生物燃料生产由于其pSOL1大质粒的丢失而受到菌株变性的损害。在这里,我们使用工程生物学将pSOL1与合成的异丙醇途径一起稳定地整合到染色体中。在连续添加葡萄糖矿物培养基的膜生物反应器中,最终菌株产生了先进的生物燃料,正丁醇和异丙醇,高产率(0.31gg-1),滴度(15.4gl-1)和生产率(15.5gl-1h-1),无变性。
    Biofuel production by Clostridium acetobutylicum is compromised by strain degeneration due to loss of its pSOL1 megaplasmid. Here we used engineering biology to stably integrate pSOL1 into the chromosome together with a synthetic isopropanol pathway. In a membrane bioreactor continuously fed with glucose mineral medium, the final strain produced advanced biofuels, n-butanol and isopropanol, at high yield (0.31 g g-1), titre (15.4 g l-1) and productivity (15.5 g l-1 h-1) without degeneration.
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  • 文章类型: Journal Article
    目的:为了研究离心法对表面特性的影响,弯曲性能,和增材制造的义齿基托聚合物的细胞毒性。
    方法:通过数字光处理(DLP)制备测试样品。使用离心法(CENT)除去残留的未固化树脂。此外,样品用不同的后冲洗溶液后处理:异丙醇(IPA),乙醇(EtOH),和三丙二醇单甲醚(TPM),分别。商业热聚合聚甲基丙烯酸甲酯用作参考(REF)。首先,表面形貌的值,算术平均高度(Sa),测量均方根高度(Sq)。接下来,评估弯曲强度(FS)和模量。最后,使用提取物试验评估细胞毒性。数据采用单向方差分析进行统计分析,其次是Tukey的多重比较测试,用于事后分析。
    结果:CENT组的Sa值低于IPA,EtOH,TPM,和REF组(p<0.001)。此外,CENT组的Sq值低于其他组(p<0.001).离心法显示出比EtOH(61.71±12.25MPa,80.92±8.65MPa)更高的FS值(80.92±8.65MPa,p<0.001)和TPM(67.01±9.751MPa,p=0.027),同时影响IPA(72.26±8.80MPa,p=0.268)和REF(71.39±10.44MPa,p=0.231)。此外,离心法无明显细胞毒作用。
    结论:用离心法处理的表面相对光滑。同时,通过离心增强了义齿基托聚合物的弯曲强度。最后,从不同的后处理程序中未观察到明显的细胞毒性作用.
    结论:离心法可以优化DLP印花义齿基托聚合物的表面质量和弯曲强度,而不影响细胞相容性,提供了一个替代传统的冲洗后处理。
    OBJECTIVE: To investigate the impact of a centrifugation method on the surface characteristics, flexural properties, and cytotoxicity of an additively manufactured denture base polymer.
    METHODS: The tested specimens were prepared by digital light processing (DLP). A centrifugation method (CENT) was used to remove the residual uncured resin. In addition, the specimens were post-processed with different post-rinsing solutions: isopropanol (IPA), ethanol (EtOH), and tripropylene glycol monomethyl ether (TPM), respectively. A commercial heat-polymerized polymethyl methacrylate was used as a reference (REF). First, the values of surface topography, arithmetical mean height (Sa), and root mean square height (Sq) were measured. Next, flexural strength (FS) and modulus were evaluated. Finally, cytotoxicity was assessed using an extract test. The data were statistically analyzed using a one-way analysis of variance, followed by Tukey\'s multiple comparison test for post-hoc analysis.
    RESULTS: The Sa value in the CENT group was lower than in the IPA, EtOH, TPM, and REF groups (p < 0.001). Moreover, the CENT group had lower Sq values than other groups (p < 0.001). The centrifugation method showed a higher FS value (80.92 ± 8.65 MPa) than the EtOH (61.71 ± 12.25 MPa, p < 0.001) and TPM (67.01 ± 9.751 MPa, p = 0.027), while affecting IPA (72.26 ± 8.80 MPa, p = 0.268) and REF (71.39 ± 10.44 MPa, p = 0.231). Also, the centrifugation method showed no evident cytotoxic effects.
    CONCLUSIONS: The surfaces treated with a centrifugation method were relatively smooth. Simultaneously, the flexural strength of denture base polymers was enhanced through centrifugation. Finally, no evident cytotoxic effects could be observed from different post-processing procedures.
    CONCLUSIONS: The centrifugation method could optimize surface quality and flexural strength of DLP-printed denture base polymers without compromising cytocompatibility, offering an alternative to conventional rinsing post-processing.
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  • 文章类型: Journal Article
    有机分子与氧化催化剂表面之间的相互作用已用于研究直接液体燃料电池中从阳极到阴极的燃料交叉。在这样的实验中,氧化表面在开路条件下与燃料接触,潜力被登记。然后,开路电势(OCP)可以告知燃料与氧化表面的反应性并提供有价值的信息。在此,我们对乙醇或2-丙醇与氧化铂表面之间的OC相互作用进行了实验研究。除了OCP,我们还采用了循环伏安法和在醇存在下的快速氧化还原扫描。在伏安图中获得了相当的反应电流,但是2-丙醇的电氧化比乙醇的过电位低得多。在高电位区,在两种情况下,电流峰值的大小和电势几乎相同。在开路条件下,乙醇与氧化铂表面的相互作用比2-丙醇更明显,这些结果被铂氧化物沿后者的快速向后扫描的容易还原所证实。
    The interaction between organic molecules and oxidized catalyst surfaces has frequently been used to study the fuel crossover from the anode to the cathode in direct liquid fuel cells. In such experiments, the oxidized surface is put in contact with the fuel under open circuit conditions, and the evolution of the potential is registered. The open circuit potential (OCP) vs. time features can then inform on the reactivity of the fuel with the oxidized surface and provide valuable information not only to applications in fuel cells but also to the electrochemical reform of those molecules to produce clean hydrogen. In this paper, we present an experimental investigation of the open circuit interaction between ethanol or 2-propanol with oxidized platinum surfaces. Besides the OCP time traces, we have also employed cyclic voltammetry and fast oxide reduction sweep in the presence of the alcohols. Comparable reaction currents are obtained in the cyclic voltammogram, but the electro-oxidation of 2-propanol sets in at considerably lower overpotentials than that of ethanol. At the high potential region, both the magnitude and the potential of the current peak are nearly identical in both cases. In contrast, under open circuit conditions, the interaction of ethanol with the oxidized platinum surface is more pronounced than that found for 2-propanol, and these results are corroborated by the facile reduction of the platinum oxides along the fast backward sweep for the case of the latter.
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  • 文章类型: Journal Article
    催化转移氢化(CTH),采用质子溶剂作为氢源来缓解分子氢H2的使用,得到了极大的关注。这项工作,报告多功能,金属Cu纳米颗粒负载ZIF-8材料,用于糠醛的CTH到高价值的燃料添加剂,使用2-丙醇的2-甲基呋喃(2-MF)。在所有合成的具有不同NaBH4浓度(yM)和Cu负载量(x)的xCu(yM)/ZIF-8催化剂中,11Cu(1.5M)/ZIF-8表现出更高的催化活性,具有>99%的FAL转化率和93.9%的2-MF选择性。这归因于其高比表面积,并且存在最佳量的Lewis酸碱位点以及Cu0物种,它们负责将糠醛氢化成糠醇,然后氢解产生2-MF。本工作报告高效稳定,FAL至2-MFCTH的金属-MOF杂化材料,这是文献中最好的报告之一,由此提出了一种有希望的生物油升级方法。
    Catalytic transfer hydrogenation (CTH), that employs protic solvents as hydrogen sources to alleviate the use of molecular hydrogen H2, has gained great attention. This work, reports multifunctional, metallic Cu nanoparticles supported ZIF-8 material for CTH of furfural to a highly valued fuel additive, 2-methylfuran (2-MF) using 2-propanol. Of all as-synthesized xCu(yM)/ZIF-8 catalysts with varied NaBH4 concentration (yM) and Cu loading (x), 11Cu(1.5 M)/ZIF-8 exhibited higher catalytic activity with > 99 % FAL conversion and 93.9 % 2-MF selectivity. This is ascribed to its high specific surface area, and existence of optimum amount of Lewis acid-base sites along with Cu0 species, which are responsible for hydrogenation of furfural to furfuryl alcohol and subsequent hydrogenolysis to produce 2-MF. The present work reports a highly efficient and stable, metal-MOF hybrid material for CTH of FAL to 2-MF, which is one among the best reports available in literature, therewith suggests a promising approach for bio-oil upgradation.
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  • 文章类型: Journal Article
    目的:经直肠超声引导下的前列腺活检(TRUS-Bx)与活检后败血症(PBS)的1-8%风险相关。最近的研究描述了显著降低PBS速率的异丙醇针头洗涤方案。当前的研究检查了该技术在我们的临床人群中的功效。
    方法:对2017年1月至2023年1月在查理诺伍德VA医学中心接受TRUS-Bx的1250名连续患者的数据进行了回顾。2021年2月采用洗针。记录TRUS-Bx后30天内发生的并发症。
    结果:第1组(未洗针)912例,第2组(洗针)338例。群体具有同等的人口统计特征,非洲裔男性占患者的70%。在第1组和第2组中分别有83%和82%的标准12个核心活检(p=0.788)。第1组和第2组的总并发症发生率分别为4%和2%(p=0.077)。第1组有13例脓毒症事件(1.4%),第2组无脓毒症事件(p=0.027)。Clavien-DindoI-III级并发症分别发生在第1组和第2组中的25例(2.7%)和7例(2.1%)患者中(p=0.505)。在第1组和第2组中,分别有80%和86%的患者接受了标准抗生素预防(PO氟喹诺酮和IM庆大霉素)(p=0.030)。仅限于接受标准预防的患者的子集分析显示,败血症发生率存在显着差异(1.5%vs0%;p=0.036)。
    结论:采用异丙醇针头清洗与PBS事件的显著减少相关。
    OBJECTIVE: Transrectal ultrasound-guided prostate biopsy (TRUS-Bx) is associated with a 1-8% risk of post-biopsy sepsis (PBS). A recent study described an isopropyl alcohol needle washing protocol that significantly decreased PBS rates. The current study examined the efficacy of this technique in our clinic population.
    METHODS: Data were reviewed for 1250 consecutive patients undergoing TRUS-Bx at the Charlie Norwood VA Medical Center from January 2017 to January 2023. Needle washing was adopted in February 2021. Complications occurring within 30 days after TRUS-Bx were recorded.
    RESULTS: There were 912 patients in group 1 (without needle washing) and 338 in group 2 (with needle washing). Groups had equivalent demographic features, and men of African descent comprised 70% of patients. Standard 12 core biopsies were done in 83% and 82% in groups 1 and 2, respectively (p = 0.788). Total complication rates were 4% and 2% in groups 1 and 2, respectively (p = 0.077). There were 13 sepsis events in group 1 (1.4%) and none in group 2 (p = 0.027). Clavien-Dindo Grade I-III complications occurred in 25 (2.7%) and 7 (2.1%) patients in groups 1 and 2, respectively (p = 0.505). Standard antibiotic prophylaxis (PO fluoroquinolone and IM gentamicin) was given in 80% and 86% of patients in groups 1 and 2, respectively (p = 0.030). Subset analysis limited to patients who received standard prophylaxis showed a significant difference in sepsis rates (1.5% vs 0%; p = 0.036).
    CONCLUSIONS: Adoption of isopropyl alcohol needle washing was associated with a significant decrease in PBS events.
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  • 文章类型: Journal Article
    我们报告了三种脂肪醇(2-丙醇,甲醇,和乙醇)和一种二醇(乙二醇)在水溶液中使用THz区域的时域椭圆计。纯液体的介电响应通过广义Debye-Lorentz方程很好地建模。对于二元混合物,我们使用修改后的有效德拜模型分析数据,考虑了H键的断裂和重整动力学以及烷基链和OH基团的运动。我们关注富水地区的属性,在非常低的溶质摩尔浓度下发现吸收特性的异常行为。这些结果,首先在THz区域观察到,与以前不同实验的发现一致,可以通过考虑醇分子的两亲性来解释。
    We report a study on the hydrogen bonding mechanisms of three aliphatic alcohols (2-propanol, methanol, and ethanol) and one diol (ethylene glycol) in water solution using a time-domain ellipsometer in the THz region. The dielectric response of the pure liquids is nicely modeled by the generalized Debye-Lorentz equation. For binary mixtures, we analyze the data using a modified effective Debye model, which considers H-bond rupture and reformation dynamics and the motion of the alkyl chains and of the OH groups. We focus on the properties of the water-rich region, finding anomalous behavior in the absorption properties at very low solute molar concentrations. These results, first observed in the THz region, are in line with previous findings from different experiments and can be explained by taking into account the amphiphilic nature of the alcohol molecules.
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