近年来,以"线上学生自学,线下教师辅导"为特点的翻转课堂引发众多教学工作者的兴趣并进行积极探索.作者通过对本校学生学习取向进行调研,基于理解学生学习行为的视角对翻转课堂进行设计,并以精馏章节翻转课堂教学为例进行展示,说明翻转课堂的实施过程及教学效果.实践证明,此方式更具教学导向性与针对性,通过开展与学情匹配的翻转课堂模式,有效调动了学生学习积极性,提升了学生的知识建构能力和实践综合能力.

学习范式理念以学生学习为中心,关注学习效果,注重学生发展.在该理念指导下,本研究构建了"多元评价,双轨驱动"的混合式教学考核评价体系,制定了细化的考评内容和评分标准.文章介绍了依托超星"一平三端"开展的化工原理课程教学考评实践,并采用定性与定量相结合的方法,从学生学习行为、学生学习效果、学生能力和学生发展四个维度分析了该考评体系的实施效果.研究结果表明,"多元评价,双轨驱动"的考评体系能够促使学生养成良好的学习习惯,发展学生乐于学习与善于学习的能力.文章还提出了持续改进过程性评价的建议,为其他专业课程的过程性评价探索提供参考.

PS 3 -PA with multi-SO 3 H exhibits excellent catalytic performance for the esterification of TMP with acrylic acid via hydrogen bond formation. The phase-separation behavior of PS 3 -PA plays an important role in catalyst recovery and stable reuse.

"互联网+"环境下,教育的信息化带来了教育理念的创新和教学模式的变革.混合式教学模式整合了教学过程中各个要素,将信息技术引入课程教与学全过程,网络在线教学和传统课堂教学相得益彰.本文依托超星学习通智慧教学工具,构建了"化工原理"课程的线上线下混合式教学模式,设计了课前线上自学,课中线下解析,课后线上提升的教学过程,并结合过程化评价和超星学习通的大数据采集,及时调整教学方式和教学活动.实践证明,混合式教学模式是当前教学过程中最有效的方式之一,对提高学生学习化工原理课程的兴趣、课程知识的掌握程度、自主学习能力和高阶思维能力均有明显促进作用.

针对化工原理课程特点和教学中存在的问题,文章提出了基于RBL模式的师生共建共享化工原理课程微信公众平台的实施方法,促使师生围绕微信公众平台的教学资源建设展开研究与学习.教师以布鲁姆教育目标分类理论为基础,将课程资源设计为"知识与释义—实践与思考—拓展与迁移"三维阶梯式框架结构;借助"互联网+"技术,通过"资源筛选—知识获取—分析探究—思考延伸"四步过程,与学生共建共享线上学习资源.实践表明,师生共建微信公众平台模式能够满足学生的个性化学习需求,提升学生的实践能力和思维能力,增强学生的学习胜任感,从而提高教学效果.

Activation of C-H bond is one of the most important scientific topics in organic synthesis area. Hydroxylation of benzene to phenol with environmentally friendly oxidants like H2O2 and O-2 is a challenge in this filed for tens of years, since it involves not only the fundamental issue of the C-sp2-H bond activation for benzene, but also other issues such as the activation of H2O2/O-2, decomposition of H2O2, and deep oxidation of phenol product. More importantly, in the context of green chemical industry , this green process becomes more attractive due to the promising alternative to replace the current cumene route. In this review, recent researches on metal-based catalysts and newly emerging non-metal catalysts are summarized, clued by the catalytic reaction mechanism of hydroxylation of benzene to phenol. The structure-activity relationship between catalysts' composition and structure with their reactive activity and selectivity is analyzed in detail based on radical and non-radical mechanisms. Outlook and suggestions on the further development of rational design of catalysts and deeper insights into reaction mechanism in this field are proposed. This review is hopefully to benefit the exploring of novel catalysts with higher activity and better stability for hydroxylation of benzene to phenol.

为实现氨氮的高效选择性转化,设计了一个氯自由基介导的电化学体系.该电化学体系以稳定性好、氧化能力强的掺硼金刚石(BDD)电极为阳极,以Pd-Cu修饰的泡沫镍材料(Pd-Cu/NF)为阴极,以氯化钠为电解质,对BDD电极选择性电催化氧化性能与机理进行了研究.结果 表明:在4.0 V电压下,体系中的Cl-原位可转化成氯自由基(Cl·),Cl·可选择性地将氨氮转化为N2和少量NO3-,副产物NO3-在Pd-Cu/NF阴极被高效还原为N2;分别探究了阴极材料、电场强度、电极间距、溶液pH和电解质种类对氨氮转化性能的影响.通过电子顺磁共振和自由基捕获实验,证实了Cl·在氨氮转化过程中发挥了重要作用.在最优条件下,可实现40 min内100％的氨氮转化率和25 mg·L-1的N2生成量,以上研究结果可为解决水体中氨氮的污染问题提供参考.

Developing a robust, porous and biodegradable scaffold remains a significant challenge in bone tissue engineering. For this purpose, biodegradable and porous hydrogel has been researched for many years. However, it is still a big challenge to get a porous and robust hydrogel in a one-step method. The objective of this study is to prepare a porous hydrogel with a triple network using chitosan and alginate cross-linked by genipin and Ca2+ respectively and a simple foaming method was utilized to enrich porous structures. Besides, the optimum dosage of foaming agents and surfactant agents is studied to prepare a porous hydrogel with suitable pore size and high mechanical strength. Furthermore, the morphology, percentage porosity, swelling property, degradation profile and biocompatibility of the porous chitosan-alginate (CA) hydrogel has been assessed. The results show that the porous hydrogel prepared in this paper has pores with size of 45-280 mu m and 91.16% porosity. The synthesis of triple network structure makes this hydrogel tough, and the wall stiffness of the dry porous CA hydrogel is 7.05 +/- 0.084 MPa. The excellent biodegradability of chitosan and alginate makes the prepared hydrogel have good biodegradability and low cytotoxicity. These properties attest that this hydrogel might be an ideal candidate for tissue engineering.

A novel modified polyepoxysuccinic acid polymer, epoxysuccinic acid-oxalic acid-allypolyethoxy carboxylate (ESA-co-APEM, PEM), was prepared through free-radical polymerization reaction of ESA and APEM and characterized by Fourier transform infrared spectroscopy.The polymer's ability to inhibit calcium sulfate scale formation, disperse ferric oxide is investigated by static tests and its corrosion inhibition performance was studied via weight loss measurements.The scale inhibition efficiency of CaSO 4 could reach 99% in the concentration of 4 mg/L, the best dispersion efficiency was reached to 20% (transmittance) when 18 mg/L of PEM was used, and the corrosion inhibition efficiency increased to 70% when the concentration was 60 mg/L.Scanning electron microscopy was used to analyze the effects of PEM on morphology of calcium sulfate and corrosion inhibition of carbon steel.The results showed that PEM possessed outstanding ability of inhibition, dispersion and corrosion inhibition properties.

An effective method for controlling scale formation in circulating cooling water system is the use of scale inhibitors. A novel multi-functional scale inhibitor AA–APES–H3PO3 terpolymer, was prepared by acrylic acid (AA), ammonium allylpolyethoxy sulfate (APES), and phosphorous acid (H3PO3) and the structural properties were identified by Fourier transform infrared and 1H-NMR. The inhibitory power of the terpolymer was determined by using a static scale inhibition method. The polymer’s effectiveness on calcium scales was assessed by using X-ray diffractometer, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It is shown that AA–APES– H3PO3 terpolymer exhibited an excellent ability to control the formation of CaCO3 scale at a mole ratio of 2/1 (AA/APES) with an inhibition efficiency of 92.6% at a level of 8 mg L–1, and at the same time, it maintained a superior efficiency even at increasing solution temperature, pH value, and Ca2+ concentration. Compared with commercial inhibitors, the order of preventing the precipitation of calcium carbonate was AA–APES–H3PO3 > EDTMP > HEDP > PESA > PAA. Also the terpolymer displayed a superior ability to prevent calcium phosphate with approximately 100% inhibition efficiency at the dosage of 6 mg L–1.

Scaling by calcium carbonate precipitation is one of the major challenges in circulating cooling water systems, which are used to transfer an amount of waste heat in industrial productive process. Calcium carbonate scale decreases the efficiency of heat transfer equipment, hinders the normal heat transfer process, and even causes the equipment layoff. Polyepoxysuccinic acid (PESA) is an environmentally friendly scaling inhibitor. In order to enhance the performance of its scale inhibition on calcium carbonate, a modified and new PESA inhibitor, epoxysuccinic acid-oxalic acid-allypolyethoxy carboxylate polyethoxy carboxylate (PEM), which contained carboxylic acid and ether groups, was synthesized. The structure of PEM was characterized, and the optimal synthesis conditions were obtained by single-factor experiments. Its scale inhibition performance was estimated with static scale inhibition methods, and the biodegradability of PEM was studied with shaking-bottle incubating test. The results indicate that when monomer ratio (n(EsA):n(ApEm) ) is 2:1, dosage of initiator is 6% and reaction temperature is 70 degrees C. The polymer PEM exhibited more excellent scale inhibition property against CaCO3 than PESA, and the comprehensive scale inhibition property of PEM is much better than the property of PESA. The scale inhibition efficiency of PEM against CaCO3 was 95.60% when the dosage was 16 mg L-1. PEM exhibited good biodegradability performance because degradation rates were more than 40% on day 10 and above 95% on day 28. The influence of PEM on formation of CaCO3 was investigated using scanning electronic microscopy and X-ray powder diffraction. The inhibition mechanism reveals that PESA chain in PEM could react with Ca2+ or crystal nucleus of CaCO3, affect the growth of CaCO3 crystals, and then distort its crystal structure. Meanwhile, there are four elements, carbon (C), hydrogen (H), oxygen (O), and sodium (Na), in its structure, without phosphorous (P), nitrogen (N), and sulphur (S), which will lead to secondary pollution to water environment, indicating that PEM is an environment-friendly calcium scale inhibitor.

Modified polyepoxysuccinic acid (PESA) scale inhibitor, ESA-co-APEM (PEM), was prepared through free-radical polymerization on PESA with oxalic acid-allypolyethoxy carboxylate, and then applied for the inhibition of calcium scales from cooling water, such as CaCO3, CaSO4, and Ca-3(PO4)(2). The structure of PEM was characterized by Fourier transform infrared (FTIR), H-1 NMR, and C-13 NMR, and the inhibition performance toward CaCO3, CaSO4, and Ca-3(PO4)(2) was studied by the method of static scale inhibition test with different dosages. The polymer PEM exhibited more excellent scale inhibition property against calcium scales than PESA and the comprehensive scale inhibition property of PEM was much better than the property of PESA. The maximum CaCO3 efficiency of PEM was as high as 94.5% in the concentration of 12 mg/L, while at a level of 4 mg/L PEM, the inhibition efficiency of CaSO4 reached 98.2%. Moreover, PEM had an efficiency of 99.5% for Ca-3(PO4)(2) at a level of 8 mg/L. The modified calcium scales in the presence of PEM were analyzed by scanning electron microscopy, X-ray powder diffraction, and transmission electron microscopy, respectively.

我们针对现阶段独立学院工程教育的现状,在遵循高等工程教育的一般规律基础上,在改革工程教育观念、重构工程培养体系、鼓励学生参加学科竞赛、提升课题制教学模式、完善校企联合培养、建立综合评价体系等方面作了初步的教学改革探索.

In the circulating cooling water systems, scale formation and stabilization of suspensions are persistent problems, which can be overcome through the use of water-soluble polymers. In this work, a new double-hydrophilic block terpolymer AA-APES-H3PO3 was synthesized from the monomers of acrylic acid (AA), ammonium allylpolyethoxy sulfate (APES), and phosphorous acid (H3PO3) with water as solvent by the free-radical polymerization. This terpolymer AA-APES-H3PO3 was characterized by Fourier-transform infrared spectrometry (FT-IR) and nuclear magnetic resonance spectroscopy. The performances of AA-APES-H3PO3 on the inhibition of CaCO3 and CaSO4 and its dispersion ability on Fe2O3 were also studied. The results show that the inhibition efficiency of AA-APES-H3PO3 is close to 93% for CaCO3 with 8 mg/L inhibitor, and reach up to 100% for CaSO4 with 4 mg/L inhibitor. The best dispersion efficiency for ferric oxide is 19.4% when AA-APES-H3PO3 is 16 mg/L. Scanning electronic microscopy, X-ray powder diffraction analysis and FT-IR were used to investigate the effect on morphology of CaCO3 and CaSO4 scales, which were highly modified in the presence of AA-APES-H3PO3. The proposed inhibition mechanism suggests that sulfo groups improved inhibitory activity and dispersion ability and showed higher calcium ion tolerance, while terpolymer containing poly(ethylene glycol) segments, -COOH, increased its solubility in water.

Metalfree photocatalytic aerobic hydroxylation of benzene to phenol is achieved by using the low-cost commercially available quinoline sulfate (QuH(2)SO(4)) as the photocatalyst. The reaction conditions are optimized and a high phenol yield of 11.3% is obtained under the optimal reaction conditions. It is found that the [QuH](+) cation is the catalytic active species and its planar structure is crucial for its effect interaction with benzene. Moreover, the influence of the coupled anion on the photocatalytic activity of the [QuH](+) cation is investigated and discussed.

To inhibit the carbonate and sulfate precipitations of calcium in cooling water systems, a water--soluble copolymer, acrylic acid-oxalic acid-methallyl methoxy polyethylene glycol-8-vinylbenzyloxy-1, 3, 6-pyrene trisulfonic acid trisodium salt (AA-HPEZ-VPTA) was synthesized. Structures of comonomer were carried out by FT-IR and 1H-NMR. The novel inhibitor's ability to control calcium scales was better than current commercial inhibitors (PAA, PESA, HPMA), with about 92.1% for CaCO3 and 98.9% for CaSO4 at levels of 8 and 4 mg/L, respectively. The effect on formation of calcium scales was investigated with combination of scanning electronic microscopy and X-ray powder diffraction analysis. The correlation coefficient r of inhibitor's is 0.9971. AA-HPEZ-VPTA can be used as an effective fluorescent- tagged scales inhibitor for cooling water systems.

本文就化工过程模拟与优化课程教学过程中出现的问题进行了分析,从改革教学方式,强化案例教学、改革考核方式、鼓励学生参加化工设计竞赛,提高学生学习兴趣、开展校企合作毕设,提升学生模拟优化的实践创新能力等几方面阐述了课程改革的过程,获得了较为显著的成效.

A non-phosphorus copolymer, acrylic acid-isoprenyl polyethoxy carboxylate copolymer (AA-TPEL) is synthesized and employed as a multifunctional scale inhibitor for calcium carbonate, calcium sulfate and calcium phosphate deposits.The molecular structure of TPEL and AA-TPEL is characterized by Fourier transform infrared spectroscopy and 1 hydrogen nuclear magnetic resonance spectroscopy.Scanning electron microscopy (SEM) and X-ray powder diffraction are used to characterize the surface morphology and crystal form of calcium scales.Compared with several current commercial inhibitors, AA-TPEL exhibits excellent ability to control calcium precipitation, with approximately 88.67% CaCO 3 inhibition and 97.07%CaSO 4 inhibition at levels of 8 and 3 mg L -1 , respectively.It also maintain superior ability to prevent the formation of Ca 3 (PO 4 ) 2 scale with 98.92% inhibition efficiency at the low level of 4 mg L -1 .The inhibitory behavior of the polymer is determined by using static scale inhibition method.

To inhibit calcium carbonate and sulfate scales in cooling water systems, a new antiscalant (acrylic acid-oxalic acid-methallyl methoxy polyethylene glycol, [AA-HPEZ]) was synthesized via radical copolymerization, and the structure of inhibitors was characterized by Fourier Transform infrared spectroscopy, hydrogen Nuclear magnetic resonance, and carbon thirteen Nuclear magnetic resonance.The ability of the polymer to mitigate the calcium carbonate and calcium sulfate scales formation was tested by static scale inhibition methods.The inhibition efficiencies of AA-HPEZ toward CaCO 3 and CaSO 4 scales were 90.6% and 100%, with 8 and 4 mg/L, respectively.The performance of copolymer on inhibition to CaCO 3 and CaSO 4 precipitation was better than poly(acrylic acid), poly(epoxysuccinic acid), and hydrolytic poly(maleic anhydride).AA-HPEZ shows great antiscaling properties for CaCO 3 scale even for the solution with higher temperature and higher hardness.

A kind of polyether-based copolymer, AA-TPEO, was synthesized using isoamyl alcohol polyoxyethylene ether, oxalic acid and acrylic acid. In this article, AA-TPEO was prepared at different mole ratios. After that, the synthesized polymer was characterized by Fourier-transform infrared (FTIR) firstly. And further verification was done through H-1 NMR. Then, the molecular weight and its distributed situation were investigated by GPC. All of above consequences demonstrated that the synthetic experiment was successful. This work mainly aimed at investigating the impact of AA-TPEO's mole ratios and the agent concentration on scale inhibition efficiency of the copolymer for CaSO4 center dot 2H(2)O and CaCO3 scales. From the results of the static scale inhibition experiments, it was known that AA-TPEO was a kind of efficient scale inhibitor. At the same time, its performance was compared with different inhibitors which were common on the market under the same conditions. The morphology and structure of deposits was confirmed by SEM, XRD and FT-IR. From the SEM photos, it could be seen that the surface appearance of CaSO4 center dot 2H(2)O and CaCO3 scales changed. The lattice of CaCO3 scales changed as the addition of AA-TPEO. The proposed inhibition mechanism of the copolymer was also described and analyzed briefly in this work.