基于Crocus模型的雪深模拟研究

雪深的准确模拟对于寒区的水文过程、气候变化、生态环境具有重要意义。积雪过程模型可以定量模拟物理环境对积雪参数的影响过程,从物理意义上定量模拟区域雪深。但是,目前积雪过程模型模拟存在参数设置复杂、不确定性大等问题。因此,有必要通过参数率定找到最适应区域的参数组合,从而完成模型参数的本地化。本文应用Crocus模型,在西藏自治区的聂拉木站、普兰站和帕里站进行3 a(2019—2021年)逐日雪深模拟,利用UQ-Pyl进行模型参数的敏感性分析及率定,构建以上站点的Crocus模型,并通过相关系数(R)、标准差比(SDC)、纳什效率系数(NSE)、平均差值(BIAS)和均方根误差(RMSE)综合评估Crocus模型在聂拉木站、普兰站和帕里站的适用性。结果表明:聂拉木站、普兰站、帕里站的Crocus模型主要敏感参数分别有20、15、13个;Crocus模型在聂拉木站的雪深模拟效果最佳(R=0.989、SDC=0.990、NSE=0.978、BIAS=0.276 cm、RMSE=4.280 cm),普兰站和帕里站次之;其中,聂拉木站的积雪沉降、积累和融化过程得到了很好的模拟,普兰站在积雪较厚时模拟效果更优,帕里站在每年3—4月时模型高估了雪深,但变化趋势基本一致,3个站点的日雪深模拟结果基本反映了雪深日变化过程。本文对Crocus模型的本地化是对积雪过程模拟研究的有益补充,为理解和揭示西藏自治区的积雪过程可提供科学依据和信息,同时,也为提高区域气候预测水平、水资源有效管理、灾害预防和应对提供有力支撑。

Saffron(Crocus sativus L.) stigmas as a potential natural additive to improve oxidative stability attributes of sunflower(Helianthus annuus L.) oil stored under different conditions

The aim of our study was to explore the antioxidant potential of Moroccan saffron stigmas(SS) and examine their performance as a natural antioxidant in enhancing the stability and quality properties of edible sunflower oil(SO), with a focus on understanding the critical importance of edible oil stability for predicting quality deterioration during storage. Bearing this in mind, our research was designed to compare the efficacy of three concentrations of dried SS(at 0.2%, 0.3%, and 0.6%) against tocobiol(a synthetic antioxidant) as a positive control(at 0.3% concentration). This comparison was conducted under three distinct storage conditions namely accelerated ageing(60 ℃), exposure to light at ambient temperature, and darkness, to evaluate their impact on preventing severe oxidation and extending oil shelf-life. Oxidation state evolution was evaluated through peroxide value(PV), free fatty acid(FFA), anisidine value(p-AV), K_(270)value(conjugated trienes), total oxidation index(TOTOX), iodine value(IV), and fatty acid composition(FA). Our results revealed notable differences in stability tracking parameters. Specifically, these parameters were higher in samples stored under accelerated conditions, followed by the samples stored in ambient light, while those stored in darkness showed the highest stability among the three storage conditions. Supplementation of sunflower oil with SS and tocobiol significantly enhanced its oxidation stability. Notably, SS exhibited exceptional effectiveness in stabilizing sunflower oil regardless of SS dose, with the highest efficacy observed at 0.6%. This was evidenced by the slower rate of oxidation parameters under various storage conditions, highlighting a superior antioxidant activity compared to both the non-enriched oil and tocobiol-enriched oil. Furthermore, saffron stigmas, used as a natural supplement,contributed to the preservation of polyunsaturated fatty acids, indicating its potential as a robust source of natural antioxidants in sunflower oil. These attributes position SS as a promising alternative to synthetic antioxidants, offering opportunities to enhance the nutritional quality and extend edible oil shelf-life.

Crocus sativus L.produces anti-inflammatory effects and regulates the NLRP3–NF-κB pathway

Objective:This study aimed to evaluate the anti-inflammatory effects of petal and stamen extracts of saffron crocus(Crocus sativus)and explore the underlying mechanism.Methods:Local and systemic inflammation models were used to investigate the anti-inflammatory effects of C.sativus.A xyleneinduced inflammation model or lipopolysaccharide(LPS)-induced inflammation model was used in this study.C.sativus petal and stamen extracts were each administered to the mice in the xylene and LPS models by gavage for 14 d at 0.1 and 0.4 g/kg doses,respectively.Enzyme-linked immunosorbent assay(ELISA)was used to measure the concentrations of tumor necrosis factor(TNF)-αand interleukin(IL)-1βin mouse serum.Hematoxylin and eosin(H&E)staining was used to observe the pathological changes in the ear in the xylene-induced inflammation model and in the spleen in the LPS-induced inflammation model.NOD-like receptor thermal protein domain associated protein 3(NLRP3)protein levels within the nuclear factor-kappa B(NF-κB)pathway were assessed using western blotting.RAW264.7 cells were treated with LPS(5μg/mL)and LPS+C.sativus(0.05,0.1,and 0.2 mg/mL)for 24 h,and a Cell Counting Kit-8 was used to measure cell proliferation.Changes in NLRP3 and NF-κB levels were evaluated by western blotting.Results:Petal and stamen extracts of C.sativus attenuated the anti-inflammatory effects in local or systemic inflammatory models and repaired pathological changes in the ear in the xylene-induced inflammation model and spleen in the LPS-induced inflammation model.These extracts also decreased the concentrations of TNF-αand IL-1βin the mouse serum in the LPS-induced inflammation model.C.sativus downregulated NLRP3 protein level through the NF-κB pathway and downregulated LC-3 and BECLIN1 in vivo and in vitro.Carbonyl Cyanide3-ChloroPhenylhydrazone(CCCP)weakened the effects of C.sativus on the NLRP3–NF-κB pathway.Conclusion:C.sativus has anti-inflammatory effects and regulates the NLRP3-NF-κB pathway.

A Medicinal and Edible Plant Crocus sativus L.and Its Therapeutic Effects on Cardiovascular and Cerebrovascular Diseases

This paper introduces the biological characteristics,medicinal value,chemical component,and pharmacological effects of Crocus sativus L.,and explores its therapeutic effects on cardiovascular and cerebrovascular diseases such as angina pectoris and coronary heart disease.

Exploring the mechanism of Crocus sativus and Rosa rugosa for the treatment of coronary heart disease based on network pharmacology and molecular docking

Coronary atherosclerotic heart disease(CHD)is the main type of cardiovascular disease.The efficacy of Uyghur drug compound Saffron formula in CHD has been clinically proven.However,the underlying mechanism remains unclear.In this study,researchers investigated the active ingredients and mechanism of action of Crocus sativus and Rosa rugosa in the treatment of CHD by network pharmacology and molecular docking techniques,collected target information with the help of TCMSP,GEO,GeneCards,and other databases,constructed protein-protein interaction(PPI)network diagrams by STRING database,performed GO and KEGG pathway enrichment analysis on common targets,and finally molecularly docked the active ingredients with core targets.C.sativus-R.rugosa have a variety of polyphenol compounds,a total of 12 active ingredients,including quercetin and kaempferol,were screened.The first three targets intersected with the core targets of CHD as AKT1,TNF,and IL-1B.Enrichment results of KEGG pathway showed that C.sativus-R.rugosa against CHD involved atherosclerosis pathways.The molecular docking results showed that quercetin and kaempferol were well bound to the core targets,and it was speculated that these components might be the main active ingredients for the treatment of CHD.The potential mechanism of action of C.sativus-R.rugosa for the treatment of coronary heart disease was initially revealed.

基于文化自信的中外合作办学学科基础课“General Chemistry”课程思政建设探索与实践

“General Chemistry”是面向中外合作办学工科专业学生开设的一门学科基础课。为了提升教学质量,课程引入国外经典教材,在教学过程中面临外来文化的冲击和文化自信缺失的风险。因此,必须通过“General Chemistry”课程思政教学提升学生对自身文化的深度认同。本文中,“General Chemistry”课程思政建设坚持文化自信理念,积极挖掘中国思政元素,将中外思政元素合理融入到教学的每一个环节,不断助推课程思政教学内涵式发展,打造课程思政高效课堂,取得了较好的育人成效。

MXenes: Versatile 2D materials with tailored surface chemistry and diverse applications

MXenes,the most recent addition to the 2D material family,have attracted significant attention owing to their distinctive characteristics,including high surface area,conductivity,surface characteristics,mechanical strength,etc.This review begins by presenting MXenes,providing insights into their structural characteristics,synthesis methods,and surface functional groups.The review covers a thorough analysis of MXene surface properties,including surface chemistry and termination group impacts.The properties of MXenes are influenced by their synthesis,which can be fluorine-based or fluorinedependent.Fluorine-based synthesis techniques involve etching with fluorine-based reagents,mainly including HF or LiF/HCl,while fluorine-free methods include electrochemical etching,chemical vapor deposition(CVD),alkaline etching,Lewis acid-based etching,etc.These techniques result in the emergence of functional groups such as-F,-O,-OH,-Cl,etc.on the MXenes surface,depending on the synthesis method used.Properties of MXenes,such as electrical conductivity,electronic properties,catalytic activity,magnetic properties,mechanical strength,and chemical and thermal stability,are examined,and the role of functional groups in determining these properties is explored.The review delves into the diverse applications of MXenes,encompassing supercapacitors,battery materials,hydrogen storage,fuel cells,electromagnetic interference(EMI) shielding,pollutant removal,water purification,flexible electronics,sensors,additive manufacturing,catalysis,biomedical and healthcare fields,etc.Finally,this article outlines the challenges and opportunities in the current and future development of MXenes research,addressing various aspects such as synthesis scalability,etching challenges,and multifunctionality,and exploring novel applications.The review concludes with future prospects and conclusions envisioning the impact of MXenes on future technologies and innovation.

Achieving asymmetric redox chemistry for oxygen evolution reaction through strong metal-support interactions

Water electrolysis poses a significant challenge for balancing catalytic activity and stability of oxygen evolution reaction(OER)electrocatalysts.In this study,we address this challenge by constructing asymmetric redox chemistry through elaborate surface OO–Ru–OH and bulk Ru–O–Ni/Fe coordination moieties within single-atom Ru-decorated defective NiFe LDH nanosheets(Ru@d-NiFe LDH)in conjunction with strong metal-support interactions(SMSI).Rigorous spectroscopic characterization and theoretical calculations indicate that single-atom Ru can delocalize the O 2p electrons on the surface and optimize d-electron configurations of metal atoms in bulk through SMSI.The^(18)O isotope labeling experiment based on operando differential electrochemical mass spectrometry(DEMS),chemical probe experiments,and theoretical calculations confirm the encouraged surface lattice oxygen,stabilized bulk lattice oxygen,and enhanced adsorption of oxygen-containing intermediates for bulk metals in Ru@d-NiFe LDH,leading to asymmetric redox chemistry for OER.The Ru@d-NiFe LDH electrocatalyst exhibits exceptional performance with an overpotential of 230 mV to achieve 10 mA cm^(−2)and maintains high robustness under industrial current density.This approach for achieving asymmetric redox chemistry through SMSI presents a new avenue for developing high-performance electrocatalysts and instills confidence in its industrial applicability.

Why the abnormal phenomena of D-band center theory exist?A new BASED theory for surface catalysis and chemistry

Since the D-band center theory was proposed,it has been widely used in the fields of surface chemistry by almost all researchers,due to its easy understanding,convenient operation and relative accuracy.However,with the continuous development of material systems and modification strategies,researchers have gradually found that D-band center theory is usually effective for large metal particle systems,but for small metal particle systems or semiconductors,such as single atom systems,the opposite conclusion to the D-band center theory is often obtained.To solve the issue above,here we propose a bonding and anti-bonding orbitals stable electron intensity difference(BASED)theory for surface chemistry.The newly-proposed BASED theory can not only successfully explain the abnormal phenomena of D-band center theory,but also exhibits a higher accuracy for prediction of adsorption energy and bond length of intermediates on active sites.Importantly,a new phenomenon of the spin transition state in the adsorption process is observed based on the BASED theory,where the active center atom usually yields an unstable high spin transition state to enhance its adsorption capability in the adsorption process of intermediates when their distance is about 2.5Å.In short,the BASED theory can be considered as a general principle to understand catalytic mechanism of intermediates on surfaces.

Teaching Status and Teaching Reform Ideas of Physical Chemistry Experiments for Food Quality and Safety Major

Physical chemistry experiments are an important branch of chemical experiments.In view of problems and shortcomings in physical chemistry experiment teaching of food quality and safety major in Chengdu University,the teaching methods of physical chemistry experiment course of food quality and safety major were explored and practiced,aiming to arouse students enthusiasm for experiments and cultivate their ability of independent learning,comprehensive thinking and independent problem solving.

Exploration of Ideological and Political Materials for the Course of Inorganic and Analytical Chemistry for Environmental and Ecological Engineering Major

Integrating ideological and political theories teaching into the whole process of classroom teaching construction is a new requirement for implementing the fundamental task of cultivating people by virtue and playing the role of collaborative education.In order to realize the seamless integration of inorganic and analytical chemistry courses and ideological and political education,this paper summarizes the current situation of ideological and political research on inorganic and analytical chemistry courses in three major databases in China(VIP,CNKI and Wanfang),and sorts out the knowledge points,ideological and political elements and educational goals according to the content of the course chapters,to provide a basic guarantee for the ideological and political education construction of the course.

Designing ultrastable P2/O3-type layered oxides for sodium ion batteries by regulating Na distribution and oxygen redox chemistry

P2/O3-type Ni/Mn-based layered oxides are promising cathode materials for sodium-ion batteries(SIBs)owing to their high energy density.However,exploring effective ways to enhance the synergy between the P2 and 03 phases remains a necessity.Herein,we design a P2/O3-type Na_(0.76)Ni_(0.31)Zn_(0.07)Mn_(0.50)Ti_(0.12)0_(2)(NNZMT)with high chemical/electrochemical stability by enhancing the coupling between the two phases.For the first time,a unique Na*extraction is observed from a Na-rich O3 phase by a Na-poor P2 phase and systematically investigated.This process is facilitated by Zn^(2+)/Ti^(4+)dual doping and calcination condition regulation,allowing a higher Na*content in the P2 phase with larger Na^(+)transport channels and enhancing Na transport kinetics.Because of reduced Na^(+)in the O3 phase,which increases the difficulty of H^(+)/Na^(+) exchange,the hydrostability of the O3 phase in NNZMT is considerably improved.Furthermore,Zn^(2+)/Ti^(4+)presence in NNZMT synergistically regulates oxygen redox chemistry,which effectively suppresses O_(2)/CO_(2) gas release and electrolyte decomposition,and completely inhibits phase transitions above 4.0 V.As a result,NNZMT achieves a high discharge capacity of 144.8 mA h g^(-1) with a median voltage of 3.42 V at 20 mA g^(-1) and exhibits excellent cycling performance with a capacity retention of 77.3% for 1000 cycles at 2000 mA g^(-1).This study provides an effective strategy and new insights into the design of high-performance layered-oxide cathode materials with enhanced structure/interface stability forSIBs.

Identified the hydrochemical and the sulfur cycle process in subsidence area of Pingyu mining area using multi-isotopes combined with hydrochemistry methods

Groundwater serves as an important water source for residents in and around mining areas.To achieve scientific planning and efficient utilization of water resources in mining areas,it is essential to figure out the chemical formation process and the ground water sulfur cycle that transpire after the coal mining activities.Based on studies of hydrochemistry and D,^(18)O-H_(2)O,^(34)S-SO_(4)isotopes,this study applied principal component analysis,ion ratio and other methods in its attempts to reveal the hydrogeochemical action and sulfur cycle in the subsidence area of Pingyu mining area.The study discovered that,in the studied area,precipitation provides the major supply of groundwater and the main water chemistry effects are dominated by oxidation dissolution of sulfide minerals as well as the dissolution of carbonate and silicate rocks.The sulfate in groundwater primarily originates from oxidation and dissolution of sulfide minerals in coal-bearing strata and human activities.The mixed sulfate formed by the oxidation of sulfide minerals and by human activities continuously recharges the groundwater,promoting the dissolution of carbonate rock and silicate rock in the process.

Defect chemistry engineering of Ga-doped garnet electrolyte with high stability for solid-state lithium metal batteries

Ga-doped Li_(7)La_(3)Zr_(2)O_(12)(Ga-LLZO)has long been considered as a promising garnet-type electrolyte candidate for all-solid-state lithium metal batteries(ASSLBs)due to its high room temperature ionic conductivity.However,the typical synthesis of Ga-LLZO is usually accompanied by the formation of undesired LiGaO_(2) impurity phase that causes severe instability of the electrolyte in contact with molten Li metal during half/full cell assembly.In this study,we show that by simply engineering the defect chemistry of Ga-LLZO,namely,the lithium deficiency level,LiGaO_(2) impurity phase is effectively inhibited in the final synthetic product.Consequently,defect chemistry engineered Ga-LLZO exhibits excellent electrochemical stability against lithium metal,while its high room temperature ionic conductivity(~1.9×10^(-3)S·cm^(-1))is well reserved.The assembled Li/Ga-LLZO/Li symmetric cell has a superior critical current density of 0.9 mA·cm^(-2),and cycles stably for 500 hours at a current density of 0.3 mA·cm^(-2).This research facilitates the potential commercial applications of high performance Ga-LLZO solid electrolytes in ASSLBs.

In Vitro Regeneration of Style-stigma-like Structure from Stamens of Crocus sativus

Style-stigma-like structures were regenerated from stamens of Crocus sativus L. The age of the stamen explant has an obvious effect on the induction rate. Auxin NAA. has larger effect on the induction of filament style-stigma-like structure. Auxin NAA of higher concentration can lead to higher induction rate. Temperature and light have different effects on the induction of style-stigma-like structure from anther's filament of C. sativus with exogenous hormones at different levels. Ultraviolet tests show that style-stigma-like structure from anther's filament of C. sativus contains crocin, safranal and picrocrocin, contents of which are obviously more than those contained in the style-stigma-like from style. Floral reversion was observed in the induction of style-stigma-like structure from petals, ovaries and styles.

番红花(Crocus sativus L.)组织培养的初步研究

目的初步探讨番红花组织培养的一些影响因素。方法采用组织培养技术,以番红花幼嫩的叶片为外植体对其愈伤组织及不定胚的诱导进行了研究结果MS+BA0.1mg/L+2,4-D2mg/L为诱导愈伤组织形成的最佳培养基,而诱导不定胚的最佳培养基为MS+BA1.5mg/L+2,4-D2mg/L。结论基本明确了番红花愈伤组织及不定胚诱导的最佳激素组合。

国外化学原理教材介绍——以Zumdahl的Chemistry(10th edition)为例

Zumdahl夫妇和DeCoste合著的Chemistry是一本在国内外广受赞誉的化学原理类教材。本文以此教材为例,介绍了国外化学原理类的教材。Chemistry这本教材内容既有广度同时也具有深度,具有可读性强、适用面广和拓展性强的特点。教材编写紧扣其培养学生化学思维和知识应用能力的基本理念,在内容和形式设计上运用了多种策略培养学生分析解决问题的能力和批判性思维能力。

国外无机化学教材的研究——以Housecroft&Sharpe的Inorganic Chemistry(5th edition)为例

Catherine Housecroft和Alan G.Sharpe合著的Inorganic Chemistry是一本经历了时间检验的经典教材,其内容涵盖了无机化学的基础原理、元素化学、生物无机化学以及这些知识在催化、工业生产和材料等领域的应用。本文希望通过对该教材的介绍及其与国内教材的编写内容和排版等的对照分析,为国内无机化学的教材编写提供一些有价值的参考,同时为从事无机化学教学的教师提供一个选择参考教材的选项。

Saffron (Crocus sativus L.) and major depressive disorder:a meta-analysis of randomized clinical trials

Due to safety concerns and side effects of many antidepressant medications, herbal psychopharmacology research has increased, and herbal remedies are becoming increasingly popular as alternatives to prescribed medications for the treatment of major depressive disorder （MDD）. Of these, accumulating trials reveal positive effects of the spice saffron （Crocus sativus L.） for the treatment of depression. A comprehensive and statistical review of the clinical trials examining the effects of saffron for treatment of MDD is warranted. OBJECTIVE： The purpose of this study was to conduct a meta-analysis of published randomized controlled trials examining the effects of saffron supplementation on symptoms of depression among participants with MDD. SEARCH STRATEGY： We conducted electronic and non-electronic searches to identify all relevant randomized, double-blind controlled trials. Reference lists of all retrieved articles were searched for relevant studies. INCLUSION CRITERIA： The criteria for study selection included the following： （1） adults （aged 18 and older） with symptoms of depression, （2） randomized controlled trial, （3） effects of saffron supplementation on depressive symptoms examined, and （4） study had either a placebo control or antidepressant comparison group. DATA EXTRACTION AND ANALYSIS： Using random effects modeling procedures, we calculated weighted mean effect sizes separately for the saffron supplementation vs placebo control groups, and for the saffron supplementation vs antidepressant groups. The methodological quality of all studies was assessed using the Jadad score. The computer software Comprehensive Meta- analysis 2 was used to analyze the data. RESULTS： Based on our pre-specified criteria, five randomized controlled trials （n = 2 placebo controlled trials, n = 3 antidepressant controlled trials） were included in our review. A large effect size was found for saffron supplementation vs placebo control in treating depressive symptoms （M ES = 1.62, P 〈 0.001）, revealing that saffron supplementation significantly reduced depression symptoms compared to the placebo control. A null effect size was evidenced between saffron supplementation and the antidepressant groups （M ES = -0.15） indicating that both treatments were similarly effective in reducing depression symptoms. The mean Jadad score was 5 indicating high quality of trials. CONCLUSION： Findings from clinical trials conducted to date indicate that saffron supplementation can improve symptoms of depression in adults with MDD. Larger clinical trials, conducted by research teams outside of Iran, with long-term follow-ups are needed before firm conclusions can be made regarding saffron＇s efficacy and safety for treating depressive symptoms.

Biochemical, Antioxidant and Antineoplastic Properties of Italian Saffron (<i>Crocus sativus L</i>.)

Saffron, the most expensive spice in the world, is got by Crocus sativus L. stigmas. The production of this substance has attracted human interest, since ancient cultures, for its medicinal and culinary properties. Because of saffron high economic value, sometimes, since Middle Ages, it is adulterated with other vegetal materials, dyes or synthetic molecules. Object of this work was the study of one of the best world saffron: Civitaretenga (AQ, Central Italy) C. sativus. Taste, color and aroma of Civitaretenga spice were determined, according to international standards (ISO/Technical Specification 3632), to define its high quality. A biochemical approach was then applied to obtain a secondary metabolite profile of this product. So, crocins, total phenolic content, flavonoids and phenolic acids were detected by HPLC-DAD and spectrophotometric analysis. Moreover, in vitro antioxidant properties and in vivo antineoplastic effects, on highly metastatic murine B16-F10 melanoma cell line, were successfully revealed in Civitaretenga C. sativus extract. All these data confirmed the elevated quality of Civitaretenga saffron and its highly reducing and chemopreventive activity.