基于OBE教育理念在“能源化学专业导论”课程教学改革中的探索

培养卓越的能源化学专业人才,既可以促进能源行业的发展,也是这类应用型理工科专业建设的重要内容。本文基于国际先进的成果导向教育(OBE)理念,以能源化学专业导论课程为例,提出一系列交叉学科专业课程教学改革探索的建议。以提升学生能力和学习成果为目的,融合OBE教育理念,注重学生知识的理解及运用,强调学生的主动参与和合作,传授学习技能和分析思维等。教学中以学生为中心,通过教学课程的实践对能源化学专业导论课程目标、能力标准、教学评估、学习资源、学习方法等进行改革,采用OBE教育理念使得能源化学课程更具有针对性和实用性,更好地掌握所学内容,并将其应用到实际生活和工作中,最终实现教学质量的提高及学生综合能力的全面提升,为新型交叉学科专业课程教学改革提供新思路。

Late Jurassic adakitic ore-bearing granodiorite porphyry intrusions in the Xiaokele porphyry Cu(–Mo)deposit,Northeast China:implications for petrogenesis and tectonic setting

The Xiaokele Cu(–Mo)deposit is a recently discovered porphyry deposit in the northern Great Xing’an Range(GXR)of northeast China.The ore bodies in this deposit are mainly hosted within granodiorite porphyry intrusions.Potassic,phyllic,and propylitic alteration zones develop from center to edge.In this paper,we present zircon LA–ICP–MS U–Pb ages,zircon Hf isotopic compositions,and whole-rock geochemistry of the ore-bearing granodiorite porphyries from the Xiaokele Cu(–Mo)deposit.Zircon U–Pb dating suggests that the Xiaokele granodiorite porphyries were emplaced at 148.8±1.1 Ma(weighted-mean age;n=14).The Xiaokele granodiorite porphyries display high SiO2,Al2O3,Sr,and Sr/Y,low K2O/Na2O,MgO,Yb,and Y,belonging to high-SiO2 adakites produced by partial melting of the subducted oceanic slab.Marine sediments were involved in the magma source of the Xiaokele granodiorite porphyries,as indicated by enriched Sr–Nd isotopic compositions(eNd(-t)=-1.17–-0.27),low positive zircon eHf(t)values(0.4–2.2),and high Th contents(4.06–5.20).The adakitic magma subsequently interacted with the mantle peridotites during ascent through the mantle wedge.The Xiaokele granodiorite porphyries were derived from slab melting during the southward subduction of the Mongol–Okhotsk Ocean.

Late Cretaceous K-rich rhyolitic crystal tuffs from the Chuduoqu area in Eastern Qiangtang subterrane:evidence for crustal thickening of the central Tibetan Plateau prior to India–Asia collision

In order to constrain whether the Lhasa–Qiangtang collision contributed to an early crustal thickening of the central Tibetan Plateau prior to the India–Asia collision,we present zircon LA–ICP–MS U–Pb ages,wholerock geochemistry,and zircon Hf isotopic compositions of the newly discovered rhyolitic crystal tuffs from the Chuduoqu area in the eastern Qiangtang subterrane,central Tibet.Zircon U–Pb dating suggests that the Chuduoqu rhyolitic crystal tuffs were emplaced at ca.68 Ma.The Chuoduoqu rhyolitic crystal tuffs display high SiO_(2) and K2 O,and low MgO,Cr,and Ni.Combined with their zircon Hf isotopic data,we suggest that they were derived from partial melting of the juvenile lower crust,and the magma underwent fractional crystallization and limited upper continental crustal assimilation during its evolution prior to eruption.They should be formed in a post-collisional environment related to lithospheric mantle delamination.The Chuduoqu rhyolitic crystal tuffs could provide important constraints on the Late Cretaceous crustal thickening of the central Tibetan Plateau caused by the Lhasa–Qiangtang collision.

Amelioration of habitat since the early Holocene contributed to the origin of agriculture in the farming-pastoral zone of northern China

The origin of agriculture in the farming-pastoral zone of northern China remains in dispute.The central region of the Inner Mongolia Plateau is located in the core area of the farming-pastoral zone;thus,it is a critical region for exploring the origin of the dryland farming system in northern China.This study selected the Yumin Site and Banan Site,which belong to the Yumin Culture-the beginning of Neolithic culture in Inner Mongolia-as the research objects.Based on the quartz optically stimulated luminescence(OSL)dating on the sedimentary sections from the Yumin site(YM)and Banan site(BN1 and BN2),the Holocene chronology framework of each section was established.After that,by identifying carbonized grains in the Yumin site and the multi-proxy analysis of each section,we investigated the relationship between the origin of agriculture and climate change in this region.The results revealed that the timing of the origin of agriculture recorded in the Yumin site lagged behind the timing of a significant increase of precipitation during the early Holocene but coincided with the timing of a significant increase of vegetation around 8.4 ka.This phenomenon was further confirmed by the published high-resolution paleoenvironmental records from the surrounding area of the Yumin Culture.We propose that with the gradual amelioration of hydrothermal conditions since the beginning of the Holocene,the regional ecosystem had been improved,resulting in the gradual conversion of the land surface from infertile sand to organic-rich soil,providing an appropriate environmental foundation for the origin of dryland farming in northern China around 8.4 ka.This study highlighted that the“accumulative environmental effects”during the early Holocene played a vital role in the origin of agriculture in northern China and provided a reference for agricultural management in the context of future climate change.

La_(2)O_(3)-promoted Ni/H-ZSM-5 catalyzed aqueous-phase guaiacol hydrodeoxygenation to cyclohexanol

Hydrodeoxygenation(HDO)of renewable lignin-derived biomass in aqueous-phase to produce high value-added products is of great significance.However,developing new catalysts with high activity and excellent stability in an aqueous phase faces considerable challenges.Rare earth doping can effectively regulate the water exchange rate constant(WERC)value of the catalyst and play an important role in promoting the hydrolysis of ether bonds.Therefore,in this paper the bimetallic supported catalyst Ni-La_(2)O_(3)/H-ZSM-5 doped with rare earth metal La_(2)O_(3)was prepared,and used to catalyze the conversion of the lignin model co mpound guaiacol to cyclohexanol in the aqueous phase.The co nversion of guaiacol catalyzed by 10Ni-3La_(2)O_(3)/H-ZSM-5 reaches 100%,and the selectivity of the product cyclohexanol is 85%.A series of characterizations illustrate that the doping of La_(2)O_(3)causes the electron transfer between La_(2)O_(3)-Ni and changes the distribution of Ni,and a strong metal carrier interaction occurs between the bimetallic Ni-La_(2)O_(3)and H-ZSM-5.This can effectively promote the hydrolysis of the C-O ether bond in guaiacol and significantly improve the activity of the catalyst.The possible catalytic reaction mechanism of Ni-La_(2)O_(3)/H-ZSM-5 catalytic conversion of guaiacol was proposed.

Synergistic effect of oxygen vacancies and edging/corner-connected MnOs structural motifs in multi-dimensional manganese oxides to enhance OvOCs catalytic oxidation

The structure-activity relationships for vinyl acetate catalytic oxidation are challenging to explore at the atomic scale due to the ambiguity of the structural defect types and sites of manganese oxides.Our work elaborates,at the atomic level,through in-situ experimental and theoretical methods,the synergistic effects of two types of structural defect sites of Vo-e(edge-sharing oxygen)and Vo-c(corner-sharing oxygen)and MnO6 structural motifs of manganese oxides.Multi-dimensional manganese oxides,namely those with corner-connected MnOs structural motifs and Vo-c structural oxygen defect sites,significantly improved the activation of vinyl acetate.Enhancement of enol structure formation,acetate and formate intermediate species,and tautomerism between enol structure and acetaldehyde were detected when oxygen vacancies of manganese oxides were present in combination with corner/edge-connected MnO6.Moreover,the activation of chemical bonds and deep catalytic oxidation of vinyl acetate depend on the presence of a redox couple,surface oxygen species,and weakened Mn-O bonds.It provides a valuable notion for investigating and designing catalytic systems and reaction processes for the purpose of emission reduction and the management of environmental contaminants.

基于自模板法构筑空心结构材料及其电化学应用

基于自模板法构筑空心结构材料,可以摆脱对常规模板法的依赖,具有合成步骤简单、重现性高、生产成本低、结构可控性好以及易于大规模制备的优点,目前引起了研究者的广泛关注.本文从颗粒内部结构调控的角度出发,主要围绕热处理诱导实心颗粒的自发空心化、选择性刻蚀具有内外结构差异的实心颗粒这两种构筑空心结构的方法进行概述,介绍了不同类型材料的自模板构筑方法及结构控制机制,结合其在钠离子及钾离子电池中的应用,探讨了空心结构材料在电化学储能领域的应用潜力,并进一步展望了自模板法构筑空心结构的前景和发展趋势.

Synergistic effects of Cu species and acidity of Cu-ZSM-5 on catalytic performance for selective catalytic oxidation of n-butylamine

In this work, a series of Cu-ZSM-5 catalysts with different SiO2/Al2O3 ratios(25, 50, 100 and200) were synthesized and investigated in n-butylamine catalytic degradation. The n-butylamine can be completely catalytic degradation at 350 ℃ over all Cu-ZSM-5 catalysts. Moreover, Cu-ZSM-5(25) exhibited the highest selectivity to N2, exceeding 90% at 350 ℃. These samples were investigated in detail by several characterizations to illuminate the dependence of the catalytic performance on redox properties, Cu species, and acidity. The characterization results proved that the redox properties and chemisorption oxygen primarily affect n-butylamine conversion. N2 selectivity was impacted by the Bronsted acidity and the isolated Cu^2+ species. Meanwhile, the surface acid sites over Cu-ZSM-5 catalysts could influence the formation of Cu species. Furthermore, in situ diffuse reflectance infrared Fourier transform spectra was adopted to explore the reaction mechanism. The Cu-ZSM-5 catalysts are the most prospective catalysts for nitrogen-containing volatile organic compounds removal, and the results in this study could provide new insights into catalysts design for VOC catalytic oxidation.

Spatial and temporal variations in prehistoric human settlement and their influencing factors on the south bank of the Xar Moron River, Northeastern China

The West Liao River Basin is the hub of ancient civilizations as well as the birthplace of rain-fed agriculture in Northern China. In the present study, based on 276 archaeological sites on the south bank of the Xar Moron River, Northeastern China, we trace the changes in prehistoric cultures as well as the shifts in the spatial and temporal patterns of human settlement in the West Liao River Basin. Location information for those sites was obtained from fieldwork. Factors such as climate change, landform evolution of the Horqin Dunefield, and sub- sistence strategies practiced at the sites were extracted via the meta-analysis of published literature. Our results show that the Holocene Optimum promoted the emergence of Neolithic Culture on the south bank of the Xar Moron River. Monsoon failure might have caused the periodic collapse or transformation of prehistoric cultures at （6.5, 4.7, 3.9, and 3.0） kyr B.P., leaving spaces for new cultural types to develop after these gaps. The rise and fall of different cultures was also determined by subsistence strategies. The Xiaoheyan Culture, with mixed modes of subsistence, weakened after 4.7 kyr B.P., whereas the Upper Xiajiadian Culture, supported by sheep breeding, expanded after 3.0 kyr B.P. Global positioning system data obtained from the archaeological sites reveal that cultures with different subsistence strategies occupied distinct geographic regions. Humans who subsisted on hunting and gathering resided at higher altitudes during the Paleolithic Age （1074 m a.s.1.）. Mixed subsistence strategies led humans to settle down at 600-1000 m a.s.1. in the Neolithic Age. Agricultural activities caused humans to migrate to 400-800 m a.s.1, in the early Bronze Age, whereas livestock production shifted human activities to 800-1200 m a.s.l, in the late Bronze Age.

Controlled synthesis of hierarchically-structured MnCo_2O_4 and its potential as a high performance anode material

To satisfy the upsurging demand for energy storage in modern society,anode materials which can deliver high capacity have been intensively researched for the next generation lithium ion batteries.Typically,the binary MnCo_2O_4 with a characteristic coupled metal cations showed promising potential due to its high theoretical capacity and low cost.Here,by means of a well-designed synthesis control,we demonstrated a scalable process to achieve a hierarchical structure of MnCo_2O_4,which existed as uniform microspheres with embedded mesopores,showing favorable structural characters for high performance during a fast charge/discharge process.Our synthesis highlighted the importance of sodium salicylate as an essential additive to control the precipitation of the two involved metal cations.It was proved that a dual role was played sodium salicylate which cannot only facilitate the formation of microspheric shape,but also act as an effective precursor for the creation of inner mesopores.We confirmed that the hierarchically-structured MnCo_2O_4 showed outstanding performance when it was tested as an anode material in lithium ion batteries as revealed by its extraordinary cycling stability and high rate capability.

Catalytic oxidation of o-chlorophenol over Co2XAI(X=Co,Mg,Ca,Ni)hydrotalcite-derived mixed oxide catalysts

A cobalt-based hydrotalcite-like compound was prepared using a constant-pH coprecipitation method.Cobalt-transition metal oxides(Co2XA10,X=Co,Mg,Ca and Ni)were investigated for the deep catalytic oxidation of o-chlorophenol as a typical heteroatom contaminant containing chlorine atoms.The partial substitution of Co by Mg,Ca or Ni in the mixed oxide can promote the catalytic oxidation of o-chlorophenol.The Co2MgA10 catalyst presented the best catalytic activity,and could maintain 90%o-chlorophenol conversion at 167.1℃,compared only 27%conversion for the Co3A10 catalyst.The results demonstrated that the high activity could be attributed to its increased low-temperature reducibility,rich active oxygen species and excellent oxygen mobility.In the existence of acid and base sites,catalysts with strong basicity also showed preferred activity.The organic by-products generated during the o-chlorophenol catalytic oxidation over Co2MgAlO catalyst included carbon tetrachloride,trichloroethylene,2,4-dichlorophenol,and 2,6-dichloro-p-benzoquinon,et al.This work provides a facile method for the preparation of Co-based composite oxide catalysts,which represent promising candidates for typical chlorinated and oxygenated volatile organic compounds.