分析化学实验多元化教学模式改革与实践

创新实验教学模式是解决当前高校理工科类实验教学困境的重要途径。总结分析化学实验教学面临的难题,依托基础性、设计型和科研型实验为教学内容,建立以微视频在线课前预习、翻转课堂的课中学习和软件联用处理实验结果的新型实验教学方法。这种多元化教学模式能有效提高学生的学习主动性和创新能力。以基础性实验和研究型实验为案例,阐述多元化教学模式的具体应用,为理工科类实验教学改革提供研究依据。

有机化学课程思政体系的构建方法与实践

理工科类专业课融入思政元素,实现知识传授的同时,发挥价值引领作用是践行“立德树人根本任务”的关键环节。基于有机化学课程教学方法改革,构建了“三个载体+四种途径”的有机化学课程思政体系,即以“理论教学、实验应用和卓越创新”三个教学模块为载体,“显性引导与隐性熏陶相结合、情境体验式、任务驱动式和专题嵌入式”为四种实现途径。并以“重氮化合物和偶氮化合物”为教学案例阐述全方位、多途径将思政元素与理论知识相融合的方法,培养出“有理想、有追求、有担当、有作为、有品质、有修养”的六有化学本科生,促进学生的全面发展。

Species profile and reactivity of volatile organic compounds emission in solvent uses,industry activities and from vehicular tunnels

A survey was conducted of the volatile organic compounds(VOCs)released from sources of solvent use,industry activities and vehicle emissions in Guiyang,a capital city of China.Samples were collected by canisters and analyzed by GC-MS-FID.The species profiles of VOCs emitted from sources were obtained.Results showed that xylenes,ethylbenzene,acetone and dichloromethane were the characteristics species for painting,2-propanol and ethyl acetate for printing,α-pinene for solid wood furniture manufacturing,and 2-butanone for biscuit baking.These characteristics species could be as tracers for the sources respectively.In most of samples from the solvent use,the benzene/toluene(B/T)ratio was less than 0.3,indicating that the ratio could be as the indicator for tracing the solvent use related sources.The results also suggested that the toluene/xylene(T/X)ratio be as the indicator to distinguish the VOCs sources of painting(<2)from the printing(>2).Aromatics contributed the most to ozone formation potential(OFP)of most painting and non-paper printing sources,and oxygen-containing VOCs(OVOCs)were major species contributing to OFP of the sources from food production and paper printing.The OFP of the VOCs emissions from vehicle in tunnels and from other manufactures were dominated by both aromatics and alkenes.Theα-pinene could explain 56.94%and 32.54%of total OFP of the VOCs sources from filing cabinet and solid wood furniture manufacturing,which was rarely been involved in previous studies of VOCs source profiles,indicating that the species of concern for VOCs sources are still insufficient at present.

国家自然科学基金委员会信息化建设现状及智能化发展展望

国家自然科学基金委员会(以下简称“自然科学基金委”)着力促进信息化与科研活动、科研管理体系的融合。随着以人工智能、大数据等智能化技术为代表的新生产力不断发展,以数据为驱动的科学基金信息化向智能化前进了一大步。本文以自然科学基金委智能化信息平台建设为主线,介绍现有信息化平台的建设情况,分析目前建设中面临的挑战,并给出在后续信息化建设中的思考与建议,充分挖掘信息技术对科学基金资助管理的主动支撑作用,促进自然科学基金委智能化建设发展。

人工智能技术在科学基金项目管理中的实践与探索

近年来,人工智能技术蓬勃发展,在多个领域取得了重大突破。国家自然科学基金委员会在深化推进科学基金系统性改革工作中,将人工智能、大数据分析等技术充分应用于科学基金项目全过程管理,依托科学基金项目管理信息系统,力图使项目申请、评审过程更加规范简约、公平公正、科学智能。本文主要介绍人工智能技术在构建科学基金知识图谱、申请书与专家画像、评审专家辅助指派等方面的实施情况,总结人工智能技术在相关管理工作中的应用经验,并进一步对基于人工智能技术的未来信息系统发展提出建议与展望。

The pollution levels, var iation character istics, sources and implications of atmospheric carbonyls in a typical rural area of North China Plain during winter

Atmospheric carbonyls were measured at a typical rural area of the North China Plain(NCP)from November 13 to December 24,2017 to investigate the pollution characteristics,sources and environmental implications.Fifteen carbonyls were detected,and formaldehyde,acetaldehyde and acetone accounted for about 81% at most.The concentration of the total carbonyls in heavily polluted days was twice more than that in clean days.In contrast to other carbonyls,m-tolualdehyde exhibited relatively high concentrations in the clean days in comparison with the polluted days.The ratios of three principal carbonyls to CO showed similar daily variations at different pollution levels with significant daytime peaks.Multiple linear regression analysis revealed that the contributions of background,primary and secondary sources to three principal carbonyls showed similar variation trends from the clean level to the heavily polluted level.The OH formation rate of formaldehyde showed a similar variation trend to its photodegradation rate,reaching the peak value at noon,which is important to maintain relatively high OH levels to initiate the oxidation of various gas-phase pollutants for secondary pollutant formation at the rural site.OH radical consumption rate and ozone formation potential(OFP) calculations showed that formaldehyde and acetaldehyde were the dominant oxidative species among measured carbonyls.As for OH radical consumption,n-butyraldehyde and m-tolualdehyde were important contributors,while for ozone formation potential,n-butyraldehyde and propionaldehyde made significant contributions.In addition,the contribution of carbonyl compounds to secondary organic aerosol(SOA) formation was also important and needs further investigation.

BLNet:Bidirectional learning network for point clouds

The key challenge in processing point clouds lies in the inherent lack of ordering and irregularity of the 3D points.By relying on per-point multi-layer perceptions(MLPs),most existing point-based approaches only address the first issue yet ignore the second one.Directly convolving kernels with irregular points will result in loss of shape information.This paper introduces a novel point-based bidirectional learning network(BLNet)to analyze irregular 3D points.BLNet optimizes the learning of 3D points through two iterative operations:feature-guided point shifting and feature learning from shifted points,so as to minimise intra-class variances,leading to a more regular distribution.On the other hand,explicitly modeling point positions leads to a new feature encoding with increased structure-awareness.Then,an attention pooling unit selectively combines important features.This bidirectional learning alternately regularizes the point cloud and learns its geometric features,with these two procedures iteratively promoting each other for more effective feature learning.Experiments show that BLNet is able to learn deep point features robustly and efficiently,and outperforms the prior state-of-the-art on multiple challenging tasks.

A highly selective turn-on colorimetric and luminescence sensor based on a triphenylamine-appended ruthenium(Ⅱ) dye for detecting mercury ion

A dual colorimetric and luminescent sensor based on a heteroleptic ruthenium dye [Ru（Hipdpa）（Hdcb- py）（NCS）2]^-.0.5H^＋ 0.5[N（C4H9）4]＋ Ru（Hipdpa） {where Hdcbpy = monodeprotonted-4,4＇-dicarboxy-2,2＇- bipyridine and Hipdpa = 4-（1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl）-N,N-diphenylaniline} for selective detection of Hg2. is presented. The results of spectrophotometric titrations revealed an evident luminescence intensity enhancement （I/Io = 11 ） and a considerable blue shift in visible absorption and luminescence maxima with the addition of rig2.. The sensitive response of the optical sensor on Hg^2＋ was attributed to the binding of the electron-deficient Hg^2＋ to the electron-rich sulfur atom of the thiocyanate （NCS） ligand in the Ru（Hipdpa）, which led to an increase in the energy gap between the highest occupied molecular orbital （HOMO） and the lowest unoccupied molecular orbital （LUMO）. Accordingly, the blue shift in the absorption spectrum of Ru（Hipdpa） due to the binding of Hg2. was obtained. Ru（Hipdpa） was found to have decreased Hg2~ detection limit and improved linear region as compared to di（tetrabutylammonium） cis-bis（isothiocyanato）bis（2,2＇-bipyridine-4-carboxylic acid-4＇- carboxylate）ruthenium（ll） N719. Moreover, a dramatic color change from pink to yellow was observed, which allowed simple monitoring of Hg^2＋ by either naked eyes or a simple colorimetric reader. Therefore, the proposed sensor can provide potential applications for Hg2＊ detection.