仪器分析实验课程思政案例设计与实践——以青蒿素的提取与结构鉴定的探究实验为例

中医药文化被喻为中华优秀传统文化的璀璨明珠,是中华传统文化的重要组成和典型代表。而作为抗疟明星的中医药青蒿素来源于天然产物,因此,天然产物中的青蒿素的提取和结构鉴定显得十分必要。课程团队结合课程特点,将青蒿素的提取和结构鉴定引入实验教学并进行课程思政教学案例设计。以此项目为载体,培养学生自主查阅文献、设计实验方案和运用仪器分析技术表征分子结构的科学素养。该教学案例的建立实施有助于教师充分挖掘课程中的思政元素,激发学生的学习兴趣,培养其自主创新意识,增强爱国情怀和民族文化自信,取得了良好的课程思政教学示范效果。

阻燃剂的层状受限分布实现聚碳酸酯/聚对苯二甲酸丁二醇酯共混物性能同步增强

聚碳酸酯/聚对苯二甲酸丁二醇酯(PC/PBT)共混物具有高表面硬度、高耐热性和耐化学性,在汽车、建筑、电子电器等领域应用广泛。但PC和PBT在阻燃体系上的差异导致共混物阻燃改性效率较低,阻燃性能较差,难以实现阻燃和力学性能的同步增强。文中采用层叠复合挤出加工制备了PC/PBT交替层状共混物,调控不同阻燃剂在交替层状共混物基体中的层状受限分布,实现了共混物阻燃性能大幅提高的同时力学性能同步增强,成功解决了PC/PBT传统共混物在高阻燃和高强度、高韧性间的矛盾。研究表明,交替层状共混物的拉伸强度和缺口冲击强度分别达到了48.1 MPa和15.8 kJ/m2,相较传统共混物分别提高了139.7%和89.7%,而且其阻燃等级达到了UL-94 V-0(1.5 mm),峰值放热率降低了11.2%。

以间歇性晕倒伴随肌阵挛发作为主要表现的分离转换障碍1例报道

分离转换障碍的特征是患者在记忆、身份意识、即时感觉和身体运动控制方面的正常整合部分或完全丧失。该文报告了1例起始症状为情绪低落、兴趣减退和面部抽动的分离转换障碍病例,随后出现间歇性晕倒伴随肌痉挛。患者多次在综合医院和精神科就诊,经多种抗抑郁药和抗癫痫药物治疗,症状未见明显改善。该案例的报道旨在加深对这类症状复杂且易误诊疾病的认识,并为类似症状患者的诊断与治疗提供参考。

光照治疗对双相抑郁的疗效与安全性的回顾与新进展

双相情感障碍(Bipolar Disorder,BD)是慢性和复发性的疾病,其中针对双相抑郁的治疗手段有限。研究发现对季节性抑郁障碍(Seasonal Affective Disorder,SAD)治疗有效的光照治疗(Light Therapy,LT)也可用于治疗双相抑郁。LT通过改善BD昼夜节律紊乱以及调节单胺类神经递质发挥抗抑郁作用。LT作为双相抑郁药物治疗的辅助手段,相对安全而有效。目前需要研究设置更规范、样本量更大、干预及随访周期更长的随机对照研究为LT治疗双相抑郁提供有力证据。

数字化赋能无机与分析化学实验的教学资源建设及应用

数字教育是推进教育高质量发展的重要途径,而数字资源的建设与应用显得尤为重要。在数字化赋能的时代背景下,我校无机与分析化学实验课程从制作教学视频资源库、开发双语版虚拟仿真实验、引进优质共享资源三方面建设教学资源,并应用于教学实践中,从而丰富数字化教学资源,推动网络教学平台的完善与混合式教学模式的改革,最终增强实验教学灵活性,促进教学形式多样性,提高课堂教学有效性。

食品王国大讲堂——“颜”之有理

以童话故事的形式,运用生动有趣的形象,通俗易懂的语言,由浅入深地引导人们透过植物性食品色彩丰富的外表以及常见的变色现象探寻其中蕴含的科学原理,从而帮助人们知其然更能知其所以然,加深对植物性食品中主要色素(叶绿素、类胡萝卜素、花青素)结构与性质(溶解性与稳定性)的认识,增强对酶促褐变的原理以及阻褐方法的了解,建立对着色剂等食品添加剂的正确观念。

“厨房化学”通识教育课程的构建与实施

通识教育是高校教育的重要组成部分,是德智体美劳五育并举的人才培养重要途径。“厨房化学”是面向我校本科生开设的化学类通识教育课程。课程融合学科知识,贴近日常生活,打造兼具学术性与趣味性的全新内容;构建多维考核体系,注重过程性考核与综合能力评判,并引入学生互评环节。该课程有效激发学生学习化学的积极性,提升化学素养,增强综合素质,同时助力科普教育发展,取得良好的教学成效。

海洋盐差能的“膜”届求职之旅

海洋盐差能发电是一项新兴的绿色能源,具有巨大的开发潜力。本文借用拟人化的手法,通过海洋盐差能在离子交换膜公司的求职之旅,简述了离子交换膜和反向电渗析技术,介绍海洋盐差能的利用现状以及被用于发电的原理。本文希望通过生动形象的语言加深读者对海洋盐差能的认识和理解,增强“能源安全”意识。

MGMT activated by Wnt pathway promotes cisplatin tolerance through inducing slow-cycling cells and nonhomologous end joining in colorectal cancer

Chemotherapy resistance plays a pivotal role in the prognosis and therapeutic failure of patients with colorectal cancer(CRC).Cisplatin(DDP)-resistant cells exhibit an inherent ability to evade the toxic chemotherapeutic drug effects which are characterized by the activation of slow-cycle programs and DNA repair.Among the elements that lead to DDP resistance,O^(6)-methylguanine(O^(6)-MG)-DNA-methyltransferase(MGMT),a DNA-repair enzyme,performs a quintessential role.In this study,we clarify the significant involvement of MGMT in conferring DDP resistance in CRC,elucidating the underlying mechanism of the regulatory actions of MGMT.A notable upregulation of MGMT in DDP-resistant cancer cells was found in our study,and MGMT repression amplifies the sensitivity of these cells to DDP treatment in vitro and in vivo.Conversely,in cancer cells,MGMT overexpression abolishes their sensitivity to DDP treatment.Mechanistically,the interaction between MGMT and cyclin dependent kinase 1(CDK1)inducing slow-cycling cells is attainted via the promotion of ubiquitination degradation of CDK1.Meanwhile,to achieve nonhomologous end joining,MGMT interacts with XRCC6 to resist chemotherapy drugs.Our transcriptome data from samples of 88 patients with CRC suggest that MGMT expression is co-related with the Wnt signaling pathway activation,and several Wnt inhibitors can repress drug-resistant cells.In summary,our results point out that MGMT is a potential therapeutic target and predictive marker of chemoresistance in CRC.

Enhanced wear resistance,antibacterial performance,and biocompatibility using nanotubes containing nano-Ag and bioceramics in vitro

A good Ti-based joint implant should prevent stress shielding and achieve good bioactivity and anti-infection performance.To meet these requirements,the low-elastic-modulus alloy—Ti–35Nb–2Ta–3Zr—was used as the substrate,and functional coatings that contained bioceramics and Ag ions were prepared for coating on TiO_(2)nanotubes(diameter:(80±20)nm and(150±40)nm)using anodization,deposition,and spin-coating methods.The effects of the bioceramics(nano-β-tricalcium phosphate,microhydroxyapatite(micro-HA),and meso-CaSiO_(3))and Ag nanoparticles(size:(50±20)nm)on the antibacterial activity and the tribocorrosion,corrosion,and early in vitro osteogenic behaviors of the nanotubes were investigated.The tribocorrosion and corrosion results showed that the wear rate and corrosive rate were highly dependent on the features of the nanotube surface.Micro-HA showed great wear resistance with a wear rate of(1.26±0.06)×10^(−3)mm^(3)/(N·m)due to adhesive and abrasivewear.Meso-CaSiO_(3)showed enhanced cell adhesion,proliferation,and alkaline phosphatase activity.The coatings that contained nano-Ag exhibited good antibacterial activity with an antibacterial rate of≥89.5%against Escherichia coli.These findings indicate that hybrid coatings may have the potential to accelerate osteogenesis.

Crc1,6RhaT is involved in the synthesis of hesperidin of the main bioactive substance in the Citrus reticulata ‘Chachi' fruit

Hesperidin is a dihydroflavonoids, accounting for more than 50% of the total flavonoids in Citri Reticulatae Pericarpium(CRP) of traditional Chinese medicine. It is an effective antioxidant and free radical scavenger that has anti-inflammatory, antiviral and hypoglycemic properties.The latest studies reported that hesperidin has a potential for novel coronavirus resistance. However, little is known about the synthesis regulation and accumulation site of hesperidin in plants. In this study, hesperidin synthase gene Crc1,6RhaT was cloned, and the protein can be completely transformed flavanone-7-O-glucoside into hesperidin in vitro and in vivo. Studies on biological characteristics of ovary walls and exocarps showed that the relative expression levels of the Crc1,6RhaT gene and protein decreased gradually with the development of citrus fruits, and the relative content of hesperidin firstly increased, then sequentially decreased. In situ hybridization results further revealed that Crc1,6RhaT transcription was mainly concentrated in the secretory cavity cells, which are revealed to be the site of flavonoid synthesis.Immunocytochemistry localization results showed that the Crc1,6RhaT was mainly located in the endoplasmic reticulum, nucleus and vacuole of secretory cells. We inferred that the Crc1,6RhaT was synthesized in the endoplasmic reticulum, then was transported into the vacuoles through enlarged vesicles at the end of the endoplasmic reticulum. Our results not only revealed that Crc1,6RhaT may be involved in the synthesis of hesperidin of the main bioactive substance in the medicinal plant Citrus reticulata ‘Chachi' fruit, but also provided novel insights into the main subcellular sites of hesperidin biosynthesis in vacuoles.

Low Surface Brightness Galaxies Selected by Different Model Fitting

We present a study of low surface brightness galaxies(LSBGs) selected by fitting the images for all the galaxies inα.40 SDSS DR7 sample with two kinds of single-component models and two kinds of two-component models(disk+bulge):single exponential,single sersic,exponential+deVaucular(exp+deV),and exponential+sérsic(exp+ser).Under the criteria of the B band disk central surface brightness μ_(0,disk)(B)≥22.5 mag arcsec^(-2) and the axis ratio b/a> 0.3,we selected four none-edge-on LSBG samples from each of the models which contain 1105,1038,207,and 75 galaxies,respectively.There are 756 galaxies in common between LSBGs selected by exponential and sersic models,corresponding to 68.42% of LSBGs selected by the exponential model and 72.83% of LSBGs selected by the sersic model,the rest of the discrepancy is due to the difference in obtaining μ_(0) between the exponential and sersic models.Based on the fitting,in the range of 0.5≤n≤1.5,the relation of μ_(0) from two models can be written as μ_(0,sérsic)-μ_(0,exp)=-1.34(n-1).The LSBGs selected by disk+bulge models(LSBG_(2)comps) are more massive than LSBGs selected by single-component models(LSBG_1comp),and also show a larger disk component.Though the bulges in the majority of our LSBG_(2)comps are not prominent,more than 60% of our LSBG_(2)comps will not be selected if we adopt a single-component model only.We also identified 31 giant low surface brightness galaxies(gLSBGs) from LSBG_(2)comps.They are located at the same region in the color-magnitude diagram as other gLSBGs.After we compared different criteria of gLSBGs selection,we find that for gas-rich LSBGs,M_(*)> 10^(10)M_⊙ is the best to distinguish between gLSBGs and normal LSBGs with bulge.

Low Surface Brightness Galaxies from BASS+MzLS with Machine Learning

From ∼5000 deg^(2) of the combination of the Beijing–Arizona Sky Survey and Mayall z-band Legacy Survey which is also the northern sky region of the Dark Energy Spectroscopic Instrument (DESI) Legacy Imaging Surveys, we selected a sample of 31,825 candidates of low surface brightness galaxies (LSBGs) with the mean effective surface brightness 24.2<μ_(eff.g)<28.8 mag arcsec^(−2) and the half-light radius 2.″5 < r_(eff)<20″ based on the released photometric catalog and the machine learning model. The distribution of the LSBGs is bimodal in the g−r color, indicating the two distinct populations of the blue (g−r< 0.60) and red (g−r> 0.60) LSBGs. The blue LSBGs appear spiral, disk or irregular while the red LSBGs are spheroidal or elliptical and spatially clustered. This trend shows that the color has a strong correlation with galaxy morphology for LSBGs. In the spatial distribution, the blue LSBGs are more uniformly distributed while the red ones are highly clustered, indicating that red LSBGs preferentially populate a denser environment than the blue LSBGs. Besides, both populations have a consistent distribution of ellipticity (median ∈∼ 0.3), half-light radius (median r_(eff) ∼ 4″) and Sérsic index (median n=1), implying the dominance of the full sample by the round and disk galaxies. This sample has definitely extended the studies of LSBGs to a regime of lower surface brightness, fainter magnitude and broader other properties than the previously Sloan Digital Sky Survey-based samples.

Astronomical Test with CMOS on the 60 cm Telescope at the Xinglong Observatory,NAOC

This work shows details of an evaluation of an observational system comprising a complementary metal-oxidesemiconductor detector, 60 cm telescope and filter complement. The system’s photometric precision and differential photometric precision, and extinction coefficients were assessed through observations of Supersky flat fields, open clusters, standard stars and exoplanets. Photometry was precision achieved at the 0.02 mag level, with differential photometry of 0.004 mag precision. Extinction was found to agree with previous studies conducted at Xinglong Observatory. Ultimately, the results demonstrate this observing system is capable of precision scientific observations with a charge-coupled device across the optical wavelengths.

基于YOLOv5算法的智能剥锌机预开口识别技术研究

预开口作业是锌电解智能剥锌系统的核心工序,预开口效果直接决定后续工序是否能够自动化连续运行。本文以矿冶科技集团研发的新一代智能剥锌机为研究对象,对智能剥锌机基本机构及开口原理进行了分析,提出了一种基于YOLOv5算法的智能剥锌机预开口识别技术,并进行了仿真分析和实验验证。实验结果表明:预开口轮廓平均识别精度达到99%,解决了智能剥锌系统无法连续化作业难题,可很好地满足生产需求,具有重要的工程应用指导意义。

基于PLC控制的自动剥锌机上料机构分布制动技术研究与应用

本文以新一代双板双工位高效自动剥锌机组为研究对象,针对上料机构运载阴极板作业过程中阴极板摆动问题进行了深入研究,提出一种基于PLC控制的自动剥锌机上料机构分布制动技术,很好地抑制了阴极板的摆动。进行了仿真分析和试验验证,结果表明:使用分步制动技术,上料机构制动时间减少了36.8%,制动距离减少了41.5%,实现了上料机构快速、高效、稳定的运载阴极板,降低了因阴极板摆动过大导致剥锌机挂取阴极板失败的故障率,大幅提升了剥锌系统工作效率。

A Localization Method of High Energy Transients for All-sky Gamma-ray Monitor

Fast and reliable localization of high-energy transients is crucial for characterizing the burst properties and guiding the follow-up observations.Localization based on the relative counts of different detectors has been widely used for all-sky gamma-ray monitors.There are two major methods for this count distribution localization:χ^(2)minimization method and the Bayesian method.Here we propose a modified Bayesian method that could take advantage of both the accuracy of the Bayesian method and the simplicity of the χ^(2)method.With comprehensive simulations,we find that our Bayesian method with Poisson likelihood is generally more applicable for various bursts than the χ^(2)method,especially for weak bursts.We further proposed a location-spectrum iteration approach based on the Bayesian inference,which could alleviate the problems caused by the spectral difference between the burst and location templates.Our method is very suitable for scenarios with limited computation resources or timesensitive applications,such as in-flight localization software,and low-latency localization for rapidly follow-up observations.

The Design of GECAM Scientific Ground Segment

The Gravitational wave burst high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)is a dedicated mission for monitoring high-energy transients.Here we report the design of the GECAM Scientific Ground Segment(GSGS)in terms of the scientific requirements,including the architecture,the external interfaces,the main function,and workflow.Judging from the analysis and verification results during the commissioning phase,the GSGS functions well and is able to monitor the status of the payloads,adjust the parameters,develop the scientific observation plans,generate the scientific data products,analyze the data,etc.Thus,the on-orbit operation and scientific researches of GECAM are guaranteed.

超高层钢筋混凝土核心筒铝模爬架技术研究

宜宾中铁卓越城项目,采用剪力墙精准固定技术和抽拉翻板固定等施工技术保证提升爬架体系的稳固,论文介绍了该项目铝模爬架技术的施工工艺原理及流程,总结了施工过程中的施工操作要点。工程效果表明,本技术效率高,节省了大量周转材料,并且经济效益显著。

基于SIMULINK的智能剥锌机剥离过程液压控制系统建模与仿真分析

智能剥离单元是智能剥锌系统中的核心装备,用于对阴极铝板上的电沉积金属锌片进行剥离。本文以某公司研发的全新一代BKAS-32型智能剥锌机的智能剥离单元为研究对象,针对其非对称液压缸控制系统的特点,建立了电液比例阀控液压系统的数学模型,设计了基于单神经元控制算法的剥离过程液压控制系统模型并进行了仿真分析,通过与传统PID控制系统的仿真结果进行对比,论证了基于单神经元控制算法的剥离过程液压控制系统性能的优越性。经过现场应用表明,应用单神经元控制算法的智能剥离单元的剥离刀具组件双向运行速度曲线平滑,对称性高,两侧剥离刀具组件的速度差小于1%,极大地增加了智能剥离单元剥离作业的稳定性。