新时代背景下省属高校本科生毕业实习-毕业论文-就业一体化教学模式探索与实践

在青岛科技大学化学专业近三届11个班306名本科生问卷调查分析的基础上,结合我校多年实践教学的探索与经验,我们构建了一套毕业实习、毕业论文及就业一体化的教学体系。本科生在企业连续从事毕业实习和毕业论文工作,表现优异者可以在企业就业。在人才培养方案中设置与实习单位有关的内容作为本科生的选修课。探索“双师型”教师队伍建设和“双导师”实践教学的途径和方法。通过校企深度合作,培养出社会需要的高技能创新型复合人才,增加就业率及就业稳定性。

创新人才培养模式,提高应用化学专业人才培养质量——以青岛科技大学为例

应用化学专业依托化学一流学科和学校化工优势,以厚基础、重交叉等理念为指导,建立了专业基础课-专业核心课-专业模块方向课三个层次的理论课程教学体系和基础实验-综合实验-专业实验-创新研究实验四个层次的实践教学体系,形成了英才培养、国际化、模块化的创新实践型人才培养模式。坚持立德树人、全面实行学业导师制,导师引领学生进行创新研究型实验探索,与专业实习与学科竞赛相结合;形成了培养理工融合、实践创新型应用化学专业人才的“3-4-3-1”培养模式。

Measurement of thermal conductivity,viscosity and density of ionic liquid [EMIM][DEP]-based nanofluids

This article studied experimentally the effect of multi-wall carbon nanotubes （MWCNTs） on the thermo physical properties of ionic liquid-based nanofluids. The nanofluids were composed of ionic liquid, 1-ethyl-3- methylimidazolium diethylphosphate [EMIM][DEP], or its aqueous solution[EMIM][DEP]（1） ＋ H20（2） and MWCNTs without any surfactants. The thermal conductivity, viscosity and density of the nanofluids were mea- sured experimentally. The effects of the mass fraction of MWCNTs, temperature and the mole fraction of water on the thermo physical properties of nanofluids were studied. Results show that the thermal conductivity of nanofluids increases within the range of 1.3%-9.7% compared to their base liquids, and have a well linear depen- dence on temperature. The viscosity and density of the nanofluids exhibit a remarkable increase compared with those of the base liquids. Finally, the correlation of the effective thermal conductivity and viscosity of the nanofluids was made using the models in the literatures.

Separation and Purification of Ginsenoside Rg1 from Triol Saponins

[Objectives] This study aimed to optimize the medium-pressure preparation process of high-purity ginsenoside Rg1 from triol saponins. [Methods] The reversed-phase C18 chromatographic separation method was used,and the purity and yield of ginsenoside Rg1 were examined as indicators. [Results]The diameter-height ratio of the C18 column was 1∶ 3. 25. Triol saponins of 0. 2 times the volume of the column were loaded with 20% ethanol. At the elution flow rate of 8 BV/h,1,3 and 0. 5 times the volume of the column was eluted with 30%,30%-40% and 40% ethanol,respectively. Crude ginsenoside Rg1 was concentrated,dissolved in 4-time-voume 95% ethanol,added with 0. 5%activated carbon,refluxed for 40 min,and dried to obtain good-quality ginsenoside Rg1. [Conclusions] After purification,ginsenoside Rg1 with purity higher than 99. 5% can be isolated from triol saponins. The medium-pressure preparation process of ginsenoside Rg1 with purity higher than 99. 5% is provided for the first time. It has been proved by many experiments that the process is stable,feasible and reproducible,and can be used for industrial scale-up production.

In situ growth of phosphorized ZIF-67-derived amorphous CoP/Cu_(2)O@CF electrocatalyst for efficient hydrogen evolution reaction

Transition metal phosphides have been extensively studied for catalytic applications in water splitting.Herein,we report an in situ phosphorization of zeolitic imidazole frameworks(ZIF-67)to generate amorphous cobalt phosphide/ZIF-67 heterojunction on a self-supporting copper foam(CF)substrate with excellent performance for hydrogen evolution reaction(HER).The needleleaf like copper hydroxide was anchored on CF surface,which acted as implantation to grow ZIF-67.The intermediate product was phosphorized to obtain final electrocatalyst(CoP/Cu_(2)O@CF)with uniform particle size,exhibiting a rhombic dodecahedron structure with wrinkles on the surface.The electrochemical measurement proved that CoP/Cu_(2)O@CF catalyst exhibited excellent HER activity and long-term stability in 1.0 mol·L^(–1)KOH solution.The overpotential was only 62 mV with the Tafel slope of 83 mV·dec^(–1)at a current density of 10 mA·cm^(–2),with a large electrochemical active surface area.It also showed competitive performance at large current which indicated the potential application to industrial water electrolysis to produce hydrogen.First-principle calculations illustrated that benefit from the construction of CoP/ZIF-67 heterojunction,the d-band center of CoP downshifted after bonding with ZIF-67 and the Gibbs free energy(ΔGH*)changed from–0.18 to–0.11 eV,confirming both decrease in overpotential and excellent HER activity.This work illustrates the efficient HER activity of CoP/Cu_(2)O@CF catalyst,which will act as a potential candidate for precious metal electrocatalysts.

Adsorption performance and physicochemical mechanism of MnO_(2)-polyethylenimine-tannic acid composites for the removal of Cu(Ⅱ) and Cr(Ⅵ) from aqueous solution

In this work,an adsorbent,which we call MnPT,was prepared by combining MnO_(2),polyethylenimine and tannic acid,and exhibited efficient performance for Cu(Ⅱ) and Cr(VI) removal from aqueous solution.The oxygen/nitrogen-containing functional groups on the surface of MnPT might increase the enrichment of metal ions by complexation.The maximum adsorption capacities of MnPT for Cu(Ⅱ) and Cr(Ⅵ) were 121.5 and 790.2 mg·g^(-1),respectively.The surface complexation formation model was used to elucidate the physicochemical interplay in the process of Cu(Ⅱ) and Cr(Ⅵ) co-adsorption on MnPT.Electrostatic force,solvation action,adsorbate-adsorbate lateral interaction,and complexation were involved in the spontaneous adsorption process.Physical electrostatic action was dominant in the initial stage,whereas chemical action was the driving force leading to adsorption equilibrium.It should be noted that after adsorption on the surface of MnPT,Cr(Ⅵ) reacted with some reducing functional groups(hydroxylamine-NH_(2))and was converted into Cr(Ⅲ).The adsorption capacity declined by 12% after recycling five times.Understanding the adsorption mechanism might provide a technical basis for the procedural design of heavy metal adsorbents.This MnPT nanocomposite has been proven to be a low-cost,efficient,and promising adsorbent for removing heavy metal ions from wastewater.