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福建海岸带与海岛乡土园林植物筛选及应用
Get PDF在查阅文献资料和实地调查的基础上,对福建省海岸带乡土园林植物进行调查和分析;采用层次分析法构建海岸带园林植物应用筛选及综合评价体系,并据此筛选出适合福建海岸带园林建设的乡土景观植物种类。构建的海岸带园林植物应用筛选体系共有一级评价指标4个,二级评价指标13个。一级指标中权重值最高的为海岸带植物适应能力,其次是应用潜力;二级指标中耐盐碱和抗风性权重值相同且最高,其次为观赏价值和资源获取。运用评价体系筛选出综合得分较高的乔木15种,灌木和草本18种,并从应用类型和观赏特色两方面对筛选出的植物进行分析。国家重点基础研发计划(闽三角城市群生态安全保障及海岸带生态修复技术:海岸带关键脆弱区生态修复与服务功能提升与示范,2016YFC0502904)泉州市科技计划项目(2016N002,2016N07
广西发现黑头鹀
Get PDF2018年10月30日清晨,在广西壮族自治区北海市银海区冠岭路旁的一片稻田(109°04’07’’N,21°27’27’’E)间的灌丛中观察到1只小型雀形目鸟类,体长较麻雀(Passer montanus)略大,约16～17 cm;嘴大而厚,呈褐色;上体灰褐色,具暗色纵纹;头顶具有明显的深色纵纹,颊和耳羽灰褐色;喉部略沾棕黄色;飞羽和尾羽褐色,翅上覆羽暗褐色并有污白色羽缘;胸腰和尾上覆羽棕黄色;下体污黄色,胸具深色纵纹;尾下覆羽明黄。经查阅相关文献和野外识别图鉴(约翰×马敬能等2000,赵正阶2001,Svensson et al. 2010,Copete 2018),确认该鸟为黑头鹀(Emberiza melanocephala)亚成体第一年冬羽或雌鸟(图1)。其与褐头鹀(E. bruniceps)雌鸟或第一年冬羽亚成体非常相似,但前额与头顶具明显的深色纵纹,腰棕黄色(赵正阶2001,Svensson et al. 2010,Copete 2018)
长期砷暴露的大鼠尿液代谢组学研究
Get PDF慢性无机砷暴露可引发多种疾病和损害,但其所涉及的生物学过程尚未完全阐明。全球约有超过2亿人面临饮用水砷污染的威胁。本研究以自由饮水的方式对健康大鼠进行无机砷的长期暴露,并对大鼠尿液的代谢组变化进行系统分析。结果表明,长期砷暴露大鼠的尿液代谢组与对照组具有显著区别,且高剂量砷暴露对大鼠尿液代谢组产生的影响更显著。本研究共鉴定出36种差异代谢物,其中14种与氨基酸代谢相关的代谢物发生了显著变化,涉及到色氨酸代谢、精氨酸和脯氨酸代谢、赖氨酸降解、β-丙氨酸代谢、半胱氨酸和蛋氨酸代谢、甘氨酸、丝氨酸和苏氨酸代谢; 11种与脂类代谢相关的代谢物,涉及到的代谢通路有鞘脂代谢、脂肪酸代谢;同时发现蛋白质的表达与翻译后修饰也受到干扰。这些生物学过程的改变均可作为砷毒性机理的关键分子事件。国家自然科学基金项目(Nos.21475110,21535007,J1310024);;\n中国博士后基金项目(No.2018M642572);;\n厦门市科技计划项目(No.3502Z20173019);;\n中央高校基本科研业务费(No.20720160051)资助~
Efficacy of UVC-LED in water disinfection on Bacillus species with consideration of antibiotic resistance issue
Get PDFAbstract(#br)Ultraviolet light emitting diode (UV-LED) has attracted extensive attention as a new technology to replace traditional mercury lamp for water disinfection. This study reported for the first time the application of UVC-LEDs in range of 200−280 nm for the treatment of two Gram-positive tetracycline resistant bacteria (TRB) from Bacillus species and their tetracycline resistant gene (TRG). The results showed that UVC-LEDs can inactivate TRB up to 5.7-log and inhibit TRG expression, especially at 268 nm. The required fluence was approximate to that of the referential non-resistant bacteria using the same UVC-LED, but far less than that of TRB using mercury lamp. After UVC-LED irradiation, photoreactivation was the dominant mechanism to repair TRB, just like non-resistant bacteria. But contrary to non-resistant bacteria, the regrowth ratio of TRB was remarkably high at 24 h since the end of the irradition, nevertheless the number of the regrown bacteria in the irradiated water was still less than that in the non-irradiated water. Whereas TRB restored resistance after repair even applying 268 nm at a fluence up to 46.08 mJ/cm 2 (maximum in this study). This study highlights the merits of UVC-LED to effectively inactivate TRB in a prompt, energy-efficient and resistance-reducing way, while future study on TRB regrowth and resistance resilience is needed
Molecularly imprinted polymer-based photonic crystal sensor array for the discrimination of sulfonamides
Get PDFAbstract(#br)In this paper, molecular imprinting and photonic crystal techniques were combined to construct a four-channel sensor array for the simultaneous identification of various sulfonamides. The assay was composed of four units. Three of these units were prepared using sulfaguanidine, sulfamethazine, or sulfathiazole as template molecules. The fourth unit was prepared without a template molecule. The preparation was optimized to obtain maximum identification with a molar ratio of template, monomer, and cross-linker of 1:50:10. The response time was as short as 10 min. For demonstration, six sulfonamides were selected as analytes. The Bragg diffraction patterns of analytes at different concentrations were measured using the sensor array. Data obtained were analyzed using linear discrimination analysis (LDA) and principal component analysis (PCA). LDA can be applied for SAs discrimination. The message ratios of 87.6%, 94.4%, and 95.8% for six SAs at 10 −4 mol L −1 , 10 −6 mol L −1 , and 10 −8 mol L −1 were achieved using LDA. The sensor array identified the mixture containing various SAs with an LDA coefficient of 86.1%, thereby indicating that the sensor array had a strong anti-interference ability. The sensor array was used to identify six SAs in fish samples. The measured data in spiked samples were consistent with the fingerprint collected from standard solutions. The accuracy rate reached 90.9%, indicating that the array can be used to identify SAs from food samples
基于WO3/AuNPs/FTO的光电化学法检测自来水中的钴离子
Get PDF建立了一种快速检测中钴离子(Co2+)的光电化学方法。首先在掺氟的SnO2透明导电玻璃（FTO）表面电沉积金纳米颗粒（AuNPs），再通过水热法在AuNPs/FTO表面生长WO3，得到WO3/AuNPs/FTO。通过扫描电镜和X射线衍射对WO3/AuNPs/FTO电极的表面形貌和晶格特征进行了表征。结果表明，AuNPs均匀分布在FTO表面，WO3呈垂直板状阵列生长。当体系中含有一定量的乙醇和Co2+时，由于Co2+与乙醇醇羟基的配位作用，抑制了乙醇捕获光生空穴的能力，对WO3/AuNPs/FTO的光电流产生明显抑制作用。在优化的条件下，光电流降低程度与Co2+浓度在0.5 ～7.0 μmol/L范围内呈线性关系，检出限为0.3 μmol/L（3s/k）)。将本方法用于自来水中Co2+含量测定，回收率为95.0% ～ 110.0%；用于维生素B12中Co2+含量的检测，测定值与国标法的结果接近，说明本方法具有较高的准确度，可望应用于实际样品中Co2+含量检测。国家自然科学基金项目(No. 21675062)福建省自然科学基金项目（No. 2017J05053）资
用于测量J偶合常数的同时多层选择性恒时J分解谱的方法（英文）
Get PDF标量偶合是核磁共振（NMR）波谱的一个重要参数.其中氢-氢偶合能提供关于分子结构的有用信息.但是,在复杂的偶合网络中解析出氢-氢偶合常数(JH-H)较为困难.本文提出了一种基于空间编码选择性恒时演化的测量JH-H的方法,利用一次实验就能解析分子中所有氢核的偶合网络,并测量JH-H.该方法被称为同时多层选择性恒时J分解谱（SMS-SECTJRES）.它结合空间编码梯度和选择性恒时演化,并利用平面回波谱成像（EPSI）采样模块,从不同的空间位置提取出对应不同氢核偶合网络的J分解谱,促进了NMR技术在分子结构解析中的进一步应用.the National Natural Science Foundation of China(U1732158 and U1632274)the Key Science and Technique Project of Fujian Province(2018Y0077)the Natural Science Foundation of Guangdong Province(2018A030313794)the Fundamental Research Funds for the Central Universities(20720170036
Evaluation of perfluoroalkyl substances in field-cultivated vegetables
Get PDFAbstract(#br)Perfluoroalkyl substances (PFASs) were investigated in three types of vegetables (fruit, leafy, and root vegetables) that were cultivated and harvested from 2014 to 2017. The cultivated soil was mainly affected by perfluoroalkyl carboxylic acid (PFCAs; 91.8% detection rate) rather than perfluoroalkyl sulfonic acids (PFSAs; 8.2%). The cultivated soil (i.e., a volcanic cohesive soil) had a high total organic carbon (TOC = 3.4%) and therefore showed strong adsorption of long-chain PFASs. Short-chain PFCAs (i.e., under C9) were mainly detected in vegetables; specifically, PFBA showed high concentration in tomato shoots. Principal component analysis (PCA) plots clearly showed that PFASs in vegetables were different from those of cultivated soil, air, and rainwater. Interestingly, the whole potato (i.e., including peel) was in the same group as soil, indicating that the whole potato can easily be affected by the cultivated soil. Energy Dispersive X-ray Spectrometry-Scanning Electron Microscope (EDS-SEM) results showed that presence of unremovable micron-sized cultivated soil particles on the potato surface. Comparing the regional differences between the cultivated area of Tsukuba city (East Japan) and Osaka city (West Japan), PFASs patterns were similar in cucumber but differed in green perilla and potato
Two Push-Pull Channels Enhance the Dinitrogen Activation by Borylene Compounds.
Get PDFRecently, Braunschweig et al found that borylene (CAAC)DurB, where CAAC is a cyclic alkyl(amino) carbene and Dur refers to 2,3,5,6-tetramethylphenyl, can bind and activate N2, and the resulting [(CAAC)DurB]2N2 is of a bent BNNB core. Since the N2 ligand in transition metal complexes is generally linear, here we probed the bonding nature of both terminal end-on and end-on bridging borylene-N2 complexes with the valence bond (VB) theory. In the terminal end-on (CAAC)HBN2 the bonding follows the mechanism in transition metals with a σ donation and a π back-donation, but in the end-on bridging borylene-N2 complex, the σ donation comes from the π orbitals of N2 and thus there are two opposite and perpendicular push-pull channels. It is the push-pull interaction that governs the enhanced activation of N2 and the BNNB bent geometry. It is expected that the substituents bonded to B can modulate the bent angle and the strength of the push-pull interaction. Indeed, (CAAC)FB exhibits enhanced catalytic capacity for the activation of N2
Coexistence of Cu(ii) and Cu(i) in Cu ion-doped zeolitic imidazolate frameworks (ZIF-8) for the dehydrogenative coupling of silanes with alcohols.
Get PDFRecently, metal-ion-doped zeolitic imidazolate frameworks have gained considerable attention for their structure tailorability and potential catalytic applications. Herein, Cu ion-doped ZIF-8 nanocrystals were successfully prepared by the mechanical grinding of Cu(NO3)2, ZnO and 2-methylimidazole (HMeIM) using ethanol as an additive. In contrast to the general view that only Cu(ii) is present in Cu-doped ZIF-8, we found the coexistence of Cu(ii) and Cu(i) in this material, which was supported by XPS and X-ray induced Auger electron spectroscopy (XAES) characterizations. Moreover, ethanol might have acted as a reducer to induce the reduction of Cu(ii) during synthesis. Due to the mixed valency of Cu ions, the Cu ion-doped ZIF-8 nanocrystals showed excellent catalytic performance in the dehydrogenative coupling of silanes with alcohols