氮掺杂鸡毛碳点荧光关开探针用于测定百草枯

以鸡毛和乙二胺为碳源和氮源,通过一步水热法合成强荧光性能的氮掺杂碳量子点(N-CQDs),并优化其制备和掺杂条件。该碳量子点具有良好的光学、结构性质和稳定性,平均粒径7.89 nm,荧光量子产率为14%。最大激发波长为320 nm,最大发射波长为386 nm。Hg²⁺存在条件下N-CQDs溶液的荧光被猝灭(关),添加百草枯后猝灭的荧光被恢复(开)。通过N-CQDs/Hg²⁺体系设计了荧光"关-开"方法,在最佳条件下,百草枯在0.05~1.0μg/mL范围内具有良好的线性,线性方程为ΔF=92.41X+123.31(R²=0.9989),检出限为16μg/L,加标回收率为95.3%~104.4%,RSD<3.8%。以鸡毛为原料制备的高选择性和灵敏性的荧光"关-开"探针方法可有效检测实际样品中的百草枯。     

Guest-dependent complexation of triptycene-derived macrotricyclic host containing one anthracene moiety with paraquat derivatives: construction of [2]rotaxanes

Complexation between the triptycene-derived macrotricyclic polyether containing an anthracene unit and paraquat derivatives in both solution and solid state was investigated. It was found that the macrotricyclic host with multi-cavity structure could form a series of [2]pseudorotaxanes with different terminal functionalised paraquat derivatives in different threading modes, which subsequently resulted in the construction of two novel [2]rotaxanes.     

液相色谱-串联质谱法快速测定植物源性食品中的百草枯

建立了水果、蔬菜、豆类和粮谷中百草枯残留的高效液相色谱-串联质谱(HPLC-MS/MS)分析方法.用水提取样品中的百草枯,弱阳离子交换(WCX)固相萃取柱(SPE)净化.采用CAPCELL PAK ST色谱柱(150 mm×2.0mm).乙腈-10 mmol/L乙酸铵水溶液(用甲酸调至pH 4.0)为流动相,以电喷雾离...     

Adventitious isolation of a pseudorotaxane complex of a trans-bis(Hydroxymethylbenzo)-27-crown-9 pyridyl cryptand and a viologen

ABSTRACT

The adventitious isolation and crystal structure of a pseudorotaxane complex of a trans-substituted dibenzo-27-crown-9-based pyridyl cryptand (6) and N,N’-dimethyl-4,4?-bipyridinium bis(hexafluorophosphate) (5) are reported.     

硫掺杂氧化锡纳米材料的固相合成及其可见光降解百草枯

以十二烷基苯磺酸钠(SDBS)为模板, 采用低温固相反应法合成了硫掺杂二氧化锡(S-SnO₂)纳米粉体材料, 并用XRD、XPS、SEM、UV-Vis、FTIR及HR-TEM等技术对材料进行了表征, 探讨了S掺杂SnO₂纳米材料对百草枯的可见光降解性能, 分析了S掺杂效应的作用机理。结果表明, 采用固相反应法所得SnO₂及S-SnO₂纳米材料的禁带宽度变窄, SDBS对材料的表面结构具有一定的调控作用。S是以S(Ⅳ)和S(Ⅵ)的形式进入SnO₂晶格形成Sn_1-xS_xO₂晶体结构而不是进入SnO₂晶格间隙, Sn-O-S键的弯曲振动峰介于930~980 cm^-1之间。S的掺杂使SnO₂纳米材料表面活性增强, 光催化降解百草枯的活性依次为SnO₂ 2(SDBS) 2 2(SDBS), 2 h内, S-SnO_2(SDBS)样品对除草剂百草枯的光催化活性达95.2%, 其主要原因是S-SnO_2(SDBS)材料表面有更多的羟基和进入SnO₂晶格的S, 有利光生电荷的有效分离。     

Dynamic Self‐Assembly Adhesion of a Paraquat Droplet on a Pillar[5]arene Surface

The adhesion of herbicide droplets on leaf surfaces plays an important role in the herbicide's adsorption by crops. How to control the adhesive binding which occurs through dynamic self‐assembly between the macroscopic droplet and the surface is a challenging task. We introduce a host onto surfaces that controls the binding of guests in the paraquat droplets. The pillar[5]arene‐functional surface showed the selective binding of paraquat droplets via the host–guest interaction. The work is promising for improving the efficiency of herbicides.     

An Electroanalytical Sensor for the Detection of Gramoxone (Paraquat)

ABSTRACT

Glassy Carbon Electrodes coated with stearic acid provide an amperometric sensor for detection of paraquat, the active ingredient of the herbicide Gramoxone. The linear dynamic range of the sensor for Paraquat is 1.02 × 10^?3 mol dm^?3 to 1.02 × 10^?2 mol dm^?3 with the minimum detection limit 6.37 × 10^?4 mol dm^?3.     

Determination of Some Herbicides by Ring-Oven Technique

Abstract

A Weisz ring-oven technique is described for estimation of some herbicides, using a combination of NaNO₂ and N-1-naphthyl-ethylenediamine dihydrochloride as a spraying reagent for amiben and methanolic NaOH for diquat and paraquat.     

新型4价离子型穴醚与一些客体的络合及理论模拟

用冠醚与类双百草枯合成了新型的4价离子型穴醚,并且初步研究了它与3个客体的络合．4价离子型穴醚与百草枯的络合作用明显．4价离子型穴醚对3个客体有选择性识别作用．分子力学模拟结果也支持了以上结论．