Biomass-derived porous carbons are regarded as promising adsorbents due to their low cost, wide availability, and environmental friendliness. However, traditional porous carbons often exhibit narrow pore-size distributions and poor pore connectivity, limiting their adsorption performance. In this study, tobacco stems (TS) were used as the carbon precursor, and CaCl2 and K2CO3 were employed as activators to construct a hierarchical porous carbon (TPC@CaCl2+K2CO3) with a high specific surface area (2437 m2 g- 1), large pore volum (1.779 cm3 g- 1), and well-connected pore channels via an in situ co-precipitation strategy. Its adsorption performance toward tetracycline hydrochloride (TCH) and the corresponding adsorption mechanism were systematically investigated. TPC@CaCl2+K2CO3 exhibits a maximum theoretical adsorption capacity of 1189 mg g- 1, surpassing most reported values for biomass-derived carbons. Mechanism analysis indicated that the efficient adsorption of TCH was governed by the synergistic contribution of pore filling, electrostatic attraction, hydrogen bonding, and pi-pi interactions. In addition, the material demonstrates strong adsorption toward multiple antibiotics, indicating broad-spectrum applicability. This work provides an effective approach for converting biomass waste into highperformance antibiotic adsorbents and offers systematic insights into the structure-performance relationship of porous carbon-based antibiotic sorbents.
It still remains a great challenge to selectively enrich and sensitively quantify the trace volatile organic compounds (VOCs) in real samples with complex matrix. In this study, an integration method combining a selective enrichment medium of reduced graphene oxide (rGO) with a specially designed micro thermal-assisted purge-and-trap sampling device was developed for efficient enrichment and sensitive quantification of trace tobacco VOCs coupling with thermal desorption (TD)-gas chromatography/mass spectrometry (GC/MS). The prepared rGO has been proved to possess excellent enrichment selectivity and capacity for tobacco polar VOCs with the multi-layer structure, good thermal stability and large specific surface area. The specially designed sampling device was efficient and suitable for enriching and sampling trace polar tobacco VOCs coupling with rGO medium. Under the optimized sampling and analytical conditions, the established analytical method could be actually applied for quantification of typical tobacco polar VOCs with the good recoveries of 72.9–128% and the satisfied RSDs of 1.8–19.9% ( n = 3). The results suggested that the developed method was selective, sensitive and reliable for enrichment and quantification of trace tobacco polar VOCs.
The use of agricultural and forestry waste to produce functional materials is a significant approach to achieving carbon neutrality. Herein, a green and cost-effective pre-oxidation and self-activation approach has been adapted to produce porous carbon from discarded tobacco stems for supercapacitors. The analysis of tobacco stem structure evolution reveals that the pre-oxidation process facilitated the cross-linked structure of the tobacco stem and the formation of KCl crystals, endowing tobacco stem-derived porous carbon with abundant micropores and high oxygen content during self-activation. The impact of pre-oxidation and self-activation temperature on the carbon structural characteristics of tobacco stems is systematically investigated. The optimized porous carbon exhibited a specific capacitance of 320 F/g at 0.5 A/g with good rate capability. Besides, it delivered a high energy density of 10.68 Wh/kg in a symmetrical supercapacitor. This work provides a green route for preparing carbon electrode materials for high-performance supercapacitors using agricultural and forestry wastes.
Macrophages in smoking environment exhibit a distinct immunosuppressive phenotype, but the mechanisms that allow nicotine to “educate” macrophages are incompletely understood. Here, we identified that nicotine transiently activates and subsequently deactivates monocytes, leading to reduced anti-infective capability of macrophages. This deactivation results in a suppression of IL-17-producing cell expansion through decreased IL-1β production. Mechanistically, nicotine induces the expression of IRAK-M in macrophages, which inhibits NF-κB signaling and restrains NLRP3 inflammasome-mediated IL-1β production. Moreover, the induction of IRAK-M by nicotine is mediated through α7 nAChR binding, which activates downstream STAT3 and AKT signaling pathways. Targeting the interaction between nicotine and α7 nAChR can decrease IRAK-M expression and restore LPS-mediated NLRP3 inflammasome-driven IL-1β production. Collectively, these findings elucidate how nicotine modulates macrophage function through complex signaling mechanisms, ultimately impacting their anti-infective responses and inflammatory processes.
磺胺二甲基嘧啶(SMZ)的大量使用会对生态环境产生不利影响,并导致耐药菌的产生,对人类健康构成重大风险.以烟梗为原料的生物炭具有价格低廉、绿色环保等优势,可用于SMZ的吸附.本文以草酸钾与碳酸钙为二元活化剂,制备了性能优异的多孔炭材料(TS-PC-800),具有最大的平衡吸附容量(852.4 mg/g).当SMZ溶液pH为3-6时,多孔炭具有良好的吸附性能,当pH为7-9时,其吸附性能显著下降.等温吸附实验和吸附动力学研究结果表明,TS-PC-800对SMZ的吸附符合Langmuir模型,吸附过程符合伪二阶动力学模型.在T=318 K,SMZ溶液初始浓度C0=200 mg/L时,其理论饱和吸附量Qm=1121mg/g,且10 min左右能快速达到吸附平衡.循环实验表明TS-PC-800具有良好的稳定性和再生性能,经过4次循环,吸附量仍可达781 mg/g.
The high-value utilization of agricultural and forestry waste holds the promise of alleviating the issues of energy crisis. Among them, the manufacturing of high-performance supercapacitor electrode materials from tobacco waste biomass is a reliable avenue. In this work, tobacco-stem-derived hierarchical porous carbon (TS-HPC) was prepared by one-pot ball milling and carbonization using calcium carbonate (CaCO3) and potassium oxalate (K2C2O4) as mild activating agents. Due to the synergistic activation of CaCO3 and K2C2O4, the specific surface area of TS-HPC is 2749 m2/g. TS-HPC with the hierarchical porous structure greatly shows an excellent specific capacitance (402 F/g at 0.5 A/g) in the three-electrode configuration. In addition, symmetric supercapacitor based on TS-HPC exhibits 10.2 W h/kg energy density at 150.0 W/kg power density, together with outstanding cycling stability (remains 97.8% after 10,000 cycles). Moreover, we demonstrated that the gas exfoliation of CaCO3 and K2C2O4 could contribute to the formation of hierarchical porous structures with a synergistic activation effect. This work could provide a new perspective on the preparation of biomass-derived carbon as electrode for supercapacitors.
为快速准确地对仓储烟叶中的曲霉菌含量进行测定,通过对几种曲霉菌的 ITS区基因序列比对找出曲霉菌属遗传保守序列,以此为靶序列设计特异性引物及 Taqman探针,构建烟曲霉基因序列重组质粒为阳性标准品,并绘制标准曲线,建立了烟叶中曲霉菌含量荧光定量PCR检测方法并验证该方法具有较好的特异性、灵敏度及重复性.利用此方法对模拟霉变烟叶进行跟踪检测,结果表明:当烟叶中曲霉菌基因拷贝数在109~1011 copies·g-1 之间时,烟叶处于临近霉变的状态;大于 1011 copies·g-1 时烟叶为霉变状态;小于109 copies·g-1 时烟叶则为未霉变状态.该研究以期为仓储烟叶的霉变情况监控提供了一种更为高效灵敏的检测方法.
为考察加热卷烟对环境空气质量的影响及其人群健康风险,采用真空辅助捕集装置捕集加热卷烟的气溶胶,结合气相色谱-氢火焰离子化检测器(GC-FID)对呼出气溶胶中主要成分(丙二醇、丙三醇、薄荷醇、烟碱、三醋酸甘油酯)进行定量分析;同时在吸烟机上模拟志愿者抽吸参数抽吸加热卷烟,测定吸入气溶胶中主要成分的释放量,并与呼出气溶胶进行比较研究.结果表明:①所建立的呼出气溶胶主要成分分析方法标准曲线线性关系良好(R2≥0.9999),检出限在0.10~0.41μg/mL之间,回收率在77.70%~120.00%之间,日内和日间精密度良好(日内RSD≤6.93%、日间RSD≤10.70%).②加热卷烟呼出气溶胶中丙二醇和丙三醇的释放量较高,且丙三醇的释放量高于丙二醇;薄荷味加热卷烟呼出气溶胶中含有薄荷醇.③加热卷烟呼出气溶胶中主要成分的释放量显著低于吸入气溶胶,人体对丙二醇、丙三醇、薄荷醇、烟碱和三醋酸甘油酯的平均截留率分别为96.80%、96.20%、96.00%、99.60%和99.60%.
目的 研究栝楼不同部位(瓜蒌皮、瓜蒌子、天花粉)对卷烟烟气总粒相物(Total particulate matter,TPM)诱导的人支气管上皮细胞(BEAS-2B)增殖以及白细胞介素6(IL-6)、白细胞介素8(IL-8)、肿瘤坏死因子α(TNF-α)表达的影响.方法 采用TPM 诱导BEAS-2B 建立细胞损伤模型.实验分为空白对照组、模型组(10 μg·mL-1TPM)、红霉素组(阳性对照,10 μg·mL-1 TPM+5 μg·mL-1红霉素)及瓜蒌皮、瓜蒌子、天花粉不同浓度给药组[10μg·mL-1TPM+400、800、1 200 ng·mL-1瓜蒌皮/瓜蒌子/天花粉(正丁醇提取物)].药物作用24 h后,采用MTT法检测细胞增殖情况;采用实时荧光定量PCR法检测细胞IL-6、IL-8、TNF-α mRNA的表达;采用ELISA法检测细胞上清液中IL-6、IL-8和TNF-α的含量.结果 与空白对照组比较,模型组的BEAS-2B细胞增殖受到明显抑制(P<0.01),细胞上清液中IL-6、IL-8和TNF-α含量明显升高(P<0.01),细胞IL-6、IL-8、TNF-α mRNA表达明显上调(P<0.01).与模型组比较,不同浓度组的瓜蒌皮、瓜蒌子、天花粉均可以促进BEAS-2B细胞的增殖(P<0.05,P<0.01);400、800、1 200 ng·mL-1瓜蒌皮组的细胞上清液中的IL-6、TNF-α含量及mRNA表达明显下调(P<0.01),800、1 200 ng·mL-1瓜蒌皮组的细胞上清液中的IL-8含量及mRNA表达明显下调(P<0.01);400、800、1 200 ng·mL-1瓜蒌子组的细胞上清液中的IL-8、TNF-α含量及mRNA表达明显下调(P<0.01);400、800、1 200ng·mL-1天花粉组的细胞上清液中的IL-6、TNF-α含量及mRNA 表达明显下调(P<0.05,P<0.01).结论 栝楼不同部位(瓜蒌皮、瓜蒌子和天花粉)正丁醇提取物可能通过促进BEAS-2B细胞增殖,抑制TNF-α、IL-6、IL-8等炎症因子表达,从而发挥其抗炎作用.
烟草挥发性有机物(Volatile organic compounds,VOCs)含量低、组成复杂、挥发性强,同时烟草及其产品基体极其复杂,发展烟草VOCs的高效采样分析技术具有重要意义.该文综述了近年来烟草VOCs分离富集介质(如石墨烯及其复合材料、硅基材料、磁性富集材料等)及相关采样技术(如QuEChERS技术、固相微萃取技术、液相微萃取技术等)的研究进展,总结了烟草VOCs分析技术在烟草产品质量控制等方面的实际应用情况,并展望了该领域的未来研究趋势.
为对烟草的最优势霉菌种类进行更具时效性的监控,本文首次提出一种霉菌酵母测试片结合NIR技术快速鉴别霉变烟叶上最优势霉菌种类的方法.将霉变烟叶上的霉菌用生理盐水稀释成不同梯度,并将稀释液制备成含菌测试片.应用NIR技术对培养后的含菌测试片进行光谱采集,获得具有不同种类最优势霉菌特征信息的近红外光谱数据.利用离散小波变换对光谱进行预处理,探究基于不同的小波基函数和小波分解层数的光谱预处理效果,运用随机森林算法构建不同最优势霉菌种类的鉴别模型.训练集识别正确率达98.25%,测试集预测正确率达99.30%,模型分类性能良好,能够用于识别常见的烟草最优势霉菌种类.本方法操作步骤简单,检测速度快,预测准确率高,为特定环境微生物种属鉴定提供了新的思路.
以吸烟室为研究对象,基于CFD模拟与步进电机实验相结合,对烟气在吸烟室中的扩散进行数值模拟,并通过P IV实验测量烟气速度进行模型验证,相对误差在25%以内.最终,得到了不同送排风方式、不同烟气源量、不同新风速度下的室内烟气速度和CO质量分数分布.结果表明:侧送上排是更加有效的净化室内烟气的送排风方式;吸烟室内不同高度的烟气浓度主要取决于送排风方式、污染源的位置;增大烟气源量,会使室内气流对流加强,气流流速加快,且室内烟气浓度较高,烟客受到二手烟的危害较高;增大新风速度是降低吸烟室内烟气浓度的有效方法.
称取再造烟叶样品0.150 0 g,加水50.0 mL并振荡提取20 min,使样品中的山梨酸根、磷酸根和柠檬酸根溶入水中.所得溶液通过0.45 μm滤膜过滤.滤液用0.25 mol·L-1 NaOH溶液调节其酸度至pH 11.0.取此溶液5 mL通过经活化的反相柱净化.弃去前3 mL流出液,收集其后的2 mL流出液,进行离子色谱分析.选用AS11-HC色谱柱为固定相,进样量为50 μL,用KOH溶液作为流动相在不同的时间段流经色谱柱进行梯度洗脱.采用自循环抑制电导检测器测定.测得山梨酸根的线性范围在0.2~4.0 mg· L-1之间,磷酸根和柠檬酸根的线性范围均在2.0~40 mg·L-1之间,其检出限(3s)依次为0.022,0.015,0.010 mg· L-1.按此方法分析3件实样,3种酸根测定值的相对标准偏差(n2=5)在0.18%~0.74%之间.在此3个样品的基础上,加入标准溶液进行回收试验,测得回收率在97.3%~103%之间.
Objective To study the anti-alcoholism effect of Puerariae lobatae radix, Puerariae lobatae flowers, Hovenia dulcis thunb mixture on acute alcohol poisoning in mice.Methods A model of acute alcoholism in mice was established by intragastrical administration of alcohol.The best ratio of each component in the mixture was identified by observing the sobering effect of the mixtures on mice.The best ratio mixture was divided into low dose group and high dose group.The mice tolerance time, drunken time, the ethanol concentration in the blood and the alcohol dehydrogenase activity in liver were measured to study the anti-alcoholism effect of the mixture.Results The Puerariae lobatae radix, Puerariae lobatae flowers, Hovenia dulcis thunb mixture not only increased the tolerance time and decreased the drunken time of mice, but also significantly reduced the ethanol concentration in blood and improved the activity of alcohol dehydrogenase in liver.Conclusion This study found that Puerariae lobatae radix, Puerariae lobatae flowers, Hovenia dulcis thunb mixture has anti-alcoholism effect on acute alcoholism in mice.
In order to investigate the alleviation effect and mechanism of Puerariae flos on acute alcoholism, a test cigarette was prepared by adding a certain amount of Puerariae flos into cut tobacco. According to the fumigation therapy theory and action mode of traditional Chinese medicines, experimental mice were treated by treatment 1 (gastric lavage with alcohol + mainstream cigarette smoke exposure) and treatment 2 (mainstream cigarette smoke exposure + gastric lavage with alcohol) separately, then the antialcoholism effects and the variations of alcohol concentration in blood and alcohol dehydrogenase activity in liver of mice were investigated. The results showed that: 1) Comparing with control groups, the drunkenness time of treatment 1 group significantly reduced when a high dosage of Puerariae flos was added into cigarette; for treatment 2 group, alcohol tolerance time remarkably increased, while drunkenness time decreased with the increase of Puerariae flos adding rate. 2) Increasing Puerariae flos adding rate raised the alcohol dehydrogenase activity in liver, while decreased the alcohol concentration in blood obviously along with the proceeding of time. Mainstream smoke of cigarette pretreated by adding Puerariae flos into cut tobacco has an obvious alleviation effect on acute alcoholism in mice.
果胶存在于植物的细胞壁和细胞内层,是植物细胞的重要组成部分,属于碳水化合物的衍生物[1]。其含量不仅影响到烟叶的理化性质,对卷烟的香气也有一定的贡献,但比例太高时会对烟叶的吸味及吸食安全性产生负面影响[2-3]。因此,测定烟叶中果胶质的含量,对监控烟草和烟草制品的品质有重要意义。