Enhancing the stability of Ni Fe-layered double hydroxide nanosheet array for alkaline seawater oxidation by Ce doping

Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability caused by detrimental chlorine chemistry.Herein,we present our recent discovery that the incorporation of Ce into Ni Fe layered double hydroxide nanosheet array on Ni foam(Ce-Ni Fe LDH/NF)emerges as a robust electrocatalyst for seawater oxidation.During the seawater oxidation process,CeO_(2)is generated,effectively repelling Cl^(-)and inhibiting the formation of Cl O-,resulting in a notable enhancement in the oxidation activity and stability of alkaline seawater.The prepared Ce-Ni Fe LDH/NF requires only overpotential of 390 m V to achieve the current density of 1 A cm^(-2),while maintaining long-term stability for 500 h,outperforming the performance of Ni Fe LDH/NF(430 m V,150 h)by a significant margin.This study highlights the effectiveness of a Ce-doping strategy in augmenting the activity and stability of materials based on Ni Fe LDH in seawater electrolysis for oxygen evolution.

Values of macular ganglion cell-inner plexiform layer and 10-2 visual field measurements in detecting and evaluating glaucoma

AIM:To assess the performance of macular ganglion cell-inner plexiform layer thickness(mGCIPLT)and 10-2 visual field(VF)parameters in detecting early glaucoma and evaluating the severity of advanced glaucoma.METHODS:Totally 127 eyes from 89 participants(36 eyes of 19 healthy participants,45 eyes of 31 early glaucoma patients and 46 eyes of 39 advanced glaucoma patients)were included.The relationships between the optical coherence tomography(OCT)-derived parameters and VF sensitivity were determined.Patients with early glaucoma were divided into eyes with or without central 10°of the VF damages(CVFDs),and the diagnostic performances of OCT-derived parameters were assessed.RESULTS:In early glaucoma,the mGCIPLT was significantly correlated with 10-2 VF pattern standard deviation(PSD;with average mGCIPLT:β=-0.046,95%CI,-0.067 to-0.024,P<0.001).In advanced glaucoma,the mGCIPLT was related to the 24-2 VF mean deviation(MD;with average mGCIPLT:β=0.397,95%CI,0.199 to 0.595,P<0.001),10-2 VF MD(with average mGCIPLT:β=0.762,95%CI,0.485 to 1.038,P<0.001)and 24-2 VF PSD(with average mGCIPLT:β=0.244,95%CI,0.124 to 0.364,P<0.001).Except for the minimum and superotemporal mGCIPLT,the decrease of mGCIPLT in early glaucomatous eyes with CVFDs was more severe than that of early glaucomatous eyes without CVFDs.The area under the curve(AUC)of the average mGCIPLT(AUC=0.949,95%CI,0.868 to 0.982)was greater than that of the average circumpapillary retinal nerve fiber layer thickness(cpRNFLT;AUC=0.827,95%CI,0.674 to 0.918)and rim area(AUC=0.799,95%CI,0.610 to 0.907)in early glaucomatous eyes with CVFDs versus normal eyes.CONCLUSION:The 10-2 VF and mGCIPLT parameters are complementary to 24-2 VF,cpRNFLT and ONH parameters,especially in detecting early glaucoma with CVFDs and evaluating the severity of advanced glaucoma in group level.

Comparison of liquid-liquid extraction-thin layer chromatography with solid-phase extraction-high-performance thin layer chromatography in detection of urinary morphine

Liquid-liquid extraction-thin layer chromatography （LLE-TLC） has been a common and routine combined method for detection of drugs in biological materials. Solid-phase extraction （SPE） is gradually replacing the tra- ditional LLE method. High performance thin layer chromatography （HPTLC） has several advantages over TLC. The present work studied the higher efficiency of a new SPE-HPTLC method over that of a routine LLE-TLC method, in extraction and detection of urinary morphine. Fifty-eight urine samples, primarily identified as mor- phine-positive samples by a strip test, ＇were re-screened by LLE-TLC and SPE-HPTLC. The results of LLE-TLC and SPE-HPTLC were then compared with each other. The results showed that the SPE-HPTLC detected 74% of total samples as morphine-positive samples whereas the LLE-TLC detected 48% of the same samples. We further discussed the effect of codeine abuse on TLC analysis of urinary morphine. Regarding the importance of morphine detection in urine, the present combined SPE-HPTLC method is suggested as a replacement method for detection of urinary morphine by many reference laboratories.

高良姜-广藿香配伍溶液的质量标准研究

目的:建立高良姜-广藿香配伍溶液的质量标准。方法:针对高良姜-广藿香配伍溶液,高良姜素、广藿香酮2种指标性成分的薄层鉴别方法分别为:薄层板为硅胶G薄层板和高效硅胶G薄层板,展开剂为石油醚-乙酸乙酯(5∶3)、(5∶1);高良姜素、广藿香酮2种指标性成分高效液相色谱含量检测方法为:色谱柱为C18色谱柱(4.6 mm×250 mm,5μm)、流动相为甲醇(A)-0.2%磷酸(B)、检测波长:310 nm、梯度洗脱。结果:对于高良姜-广藿香配伍溶液中高良姜素、广藿香酮2种指标性成分,薄层鉴别主斑点清晰、阴性对照无干扰;2种指标性成分的浓度在10.00~1000.00μg/mL、10.00~640.00μg/mL范围内与峰面积线性关系系数分别为R^(2)=0.9990、R^(2)=0.9999;精密度RSD分别为0.63%、0.56%,稳定性RSD分别为1.82%、0.24%,重复性RSD分别为1.30%、0.89%;平均回收率分别为103.19%、100.87%(RSD为别为0.93%、0.4%,n=9);该2种指标性成分的含量应分别不低于233.71μg/mL、61.48μg/mL。结论:建立的方法可用于高良姜-广藿香配伍溶液的质量控制,该方法精密度、准确度、稳定性及重复性均符合要求。

Preparation Process and Thin Layer Chromatography Identification of Wufang Babu Poultice

[Objectives] To establish the process flow of preparation of Wufang Babu Poultice and the identification method of thin layer chromatography (TLC). [Methods] For the forming process of Wufang Babu Poultice, the preparation method of mixed pharmaceutical powder with suitable pharmaceutical excipients was adopted. Qualitative identification of medicinal materials in Wufang Babu Poultice (Strychni Semen, Rhei Radix Et Rhizoma, Dipsaci Radix, and Angelicae Sinensis Radix) was carried out by TLC. [Results] Mixed pharmaceutical powder mixed with glycerol, gelatin and other pharmaceutical excipients can be prepared for forming. The test solution chromatography of each medicinal material (Strychni Semen, Rhei Radix et Rhizoma, Dipsaci Radix, Angelicae Sinensis Radix) showed pigment spots of the same color at the same position as its corresponding control medicinal materials and reference chromatography, and the display was clear. [Conclusions] The preparation process is simple and feasible, and can be used as the forming process of Wufang Babu Poultice. The TLC determination method is simple to operate, has good specificity, and has no effect on negative results, and can be used for identification of Wufang Babu Poultice.

黏细菌A96-1产埃博霉素B的鉴定及其发酵培养基优化

目的 筛选埃博霉素B产生菌,并优化发酵培养基,以提高发酵产量。方法 利用高效液相色谱法和薄层色谱法对次级代谢产物进行分析鉴定,从实验室保存的菌库中筛选出埃博霉素B产生菌,再通过单因素实验和正交试验优化发酵培养基成分。结果 获得1株产埃博霉素B的黏细菌A96-1,采用优化后的发酵培养基:马铃薯淀粉6 g/L,玉米浆干粉2 g/L,CaCl_22 g/L,MgSO_4·7H_2O 3 g/L,微量元素溶液1 mL/L,树脂添加量2%,埃博霉素B发酵产量为251.4 mg/L,较优化前提高了3.83倍。结论通过菌株筛选和优化的培养基大幅提高了埃博霉素B的产量,为今后其资源开发利用及产业化提供参考。

Thin Layer Chromatographic Study of Bauxite and Quantitative Estimation of Co-Existing Al^(3+), Fe^(2+) and Ti^(4+)

Thin layer chromatography in combination with spectrophotometry and titrimetry has been used to evaluate chromatographic characteristics of bauxite constituents. The retention behaviors of four major constituents (Al 3+ , Fe 2+ , Ti 4+ , Si 4+ ) in bauxite mineral have been examined on plain and modified layers of silica gel G, silica gel H and cellulose with mobile phases containing aqueous sodium chloride, formic acid and hydrochloric acid. Ternary separation of Al-Fe-Ti was achieved on chromatographic plates made of silica gel H. The pH effect and presence of impurity elements in samples, nature of stationary phases on the ternary separation and detection limits of bauxite constituents were studied. Silicon in bauxite was detected on cellulose plates. Quantitative determinations of Al 3+ , Fe 2+ and Ti 4+ on silica gel H impregnated with sodium formate layers were achieved by titrimetry and spectrophotometry.

TLC联合UPLC-QQQ-MS分析天王补心丸中4种外源性污染成分

目的对天王补心丸质量分析中发现的异常成分进行研究,建立薄层色谱(TLC)、超高效液相色谱—三重四极杆质谱(UPLC-QQQ-MS)同时测定天王补心丸中盐酸小檗碱、表小檗碱、盐酸黄连碱、盐酸巴马汀等4种外源性污染成分的分析方法。方法采用TLC法,通过优化展开系统,对158批样品进行定性鉴别;针对异常斑点,采用HPLC-Q/TOF-MS进行成分鉴定确认;采用UPLC-QQQ-MS进行定量分析。结果158批天王补心丸样品中有9批检出盐酸小檗碱、表小檗碱、盐酸黄连碱、盐酸巴马汀等4种外源性污染成分,分别在0.97~483.34、0.98~98.49、1.00~100.50、0.88~87.75ng·mL^(-1)内呈线性,回收率为99.30%~103.99%,平均标准偏差(RSD)为0.90%~2.62%(n=6),9批样品中上述4种成分的含量分别为20.3~104.1、1.0~17.6、0.4~30.6、3.2~24.8μg·g^(-1)。结论该方法简便、准确、专属性强,可为天王补心丸的质量控制提供参考。

顶空/气相色谱-质谱联用法测定塑胶跑道面层中46种挥发性有机化合物

建立了测定塑胶跑道面层中46种挥发性有机化合物(VOCs)的顶空/气相色谱-质谱联用(HS/GC-MS)法。样品剪碎后加入三乙酸甘油酯,顶空进样,目标物经DB-624UI毛细管色谱柱分离后,在电子轰击源(EI)下进行选择离子扫描(SIM)定性分析,外标法定量。分别对色谱柱、升温程序、顶空参数和分散溶剂进行了优化。结果表明,在最优条件下,46种VOCs在各自质量浓度范围内线性关系良好,相关系数(r^(2))均大于0.995,方法检出限(LOD)和定量下限(LOQ)分别为0.05~0.60μg/g和0.10~1.20μg/g,在3个不同加标水平下的平均加标回收率为82.9%~114%,相对标准偏差(RSD,n=6)为1.1%~5.6%。该方法前处理简单、检出限低、准确度高,满足塑胶跑道面层中VOCs快速定性定量分析的要求。

Quality Evaluation of Leontopodium franchetii Beauv. from Different Localities Based on Moisture,Ash and Extract Contents and Thin-layer Chromatography

[Objectives] The aim was to determine the moisture,ash and extract contents in Leontopodium franchetii Beauv. from different localities. [Methods] The contents of moisture,total ash,acid-insoluble ash and extract in L. franchetii from different localities were determined according to the methods described in Chinese Pharmacopoeia( 2015 Edition). [Results] In the 10 samples,the contents of moisture were all less than or equal to 15. 0%; the contents of total ash were all below 12. 0%; and the contents of acid-insoluble ash were all less than 3. 0%. The contents of water-soluble extract( by cold-soaked extraction method) in the samples were all below 12. 0% except those from Hongyuan Prairie of Sichuan Province and Xinglong Mountain in Lanzhou City,Gansu Province. [Conclusions]The contents of the four indicators measured in this experiment varied by small margins,indicating that the quality was relatively stable. This study provides theoretical data for the revision of the quality standards for L. franchetii.

Novelties Filtration Theory of Liquid Chromatography-Mass Spectrometry in Volume Nanotube of Cotton Filament of Layers Woven Fabrics

Objectives of the research to present a modern theory of water purification for multiple purposes entitled “a novelties filtration theory of liquid chromatography-mass spectrometry” is an exceedingly sensitive and specific analytical technique in volume layers woven fabrics that can precisely determine the identities and quantities of compounds within volume Nanotube of cotton filament of layers woven fabrics. The problems are that the filters in the local and international markets have increased complications in configuration, installation and cost without reaching the efficiency that humanity hopes. Throw materials and methods the chromatography-mass spectrometry in layers woven fabrics, and throw the nanotube of cotton filament for purification of water dyes and smells. Industry, in which mass spectrometry is a convenient, versatile method for characterization and identification of process throw the Nanotube of cotton filament for purification of water dyes and smells. Results came up with a theme “innovations in textiles”, and also, for characterization of fibers and contaminants of the fabrics. Additive manufacturing in layers woven fabrics, are the processes used to synthesize a volume object under computer control with successive material layers that have been used and highlighted. The conclusions has included chromatography-mass spectrometry drop, physico-chemical, biological, combined physical-biological and chemical-biological treatment processes recently being developed to meet Jet-filtration, the strict discharging limits set by ASTM standards. Some important aspects of both qualitative and quantitative data analysis have been described and the power of using mass profiles to enhance selectivity and sensitivity has been demonstrated.

Separation of Amino Acids Based on Thin-Layer Chromatography by a Novel Quinazoline Based Anti-Microbial Agent

A newly designed quinazoline based compound, 6-pyridin-2-yl-5,6-dihydro-benzo[4,5]imidazo[1,2-c] quinazoline (PDBIQ) has shown the ability for the easy detection of nineteen amino acids on thin-layer chromatography plates as a spray reagent. This new reagent enabled to produce various distinguishable colors with amino acids with different RF values. The detection limits and the binding ability of PDBIQ with amino acids have been calculated. PDBIQ is also able to detect aminoacids from hydrolised seed protein. The title compound also exhibited profound inhibitory action against some gm (+ve) and gm (-ve) bacterial organisms. This paper deals with synthesis, spectroscopic application and biological evaluation of the organic moity.

TLC-FID法测定延迟焦化原料油族组成

用三种不同极性展开剂在棒状薄层色谱棒上较好地将延迟焦化原料油分离为饱和烃、芳烃、胶质和沥青质四个族组分,建立了用棒状薄层色谱法-氢焰检测器(TLC-FID)快速测定延迟焦化原料油族组成的方法。通过重复性试验考察本方法的精密度,四组分相对标准偏差均小于3.00%,极差值均小于3.50%。

Secondary metabolite credentials ofEvolvulus alsinoides by high performance thin layer chromatography(HPTLC)

Plants and plant-based products are the bases of many modern pharmaceuticals that are current in use today for various diseases.The aim of the study was to investigate the biochemical constituents and high performance thin layer chromatography（HPTLC） finger printing of the ethanolic extract of Evolvulus alsinoides.Phytochemical screening was done by standard procedures and HPTLC method was also established to analyze alkaloids,flavonoids and phenolic compounds from the ethanolic extract of Evolvulus alsinoides.Preliminary phytochemical screening showed that ethanol extracted more secondary metabolites than other solvents.HPTLC fingerprinting analysis showed the presence of various alkaloids,flavonoids and phenols（quercetin） in the ethanolic extract.It can be concluded that Evolvulus alsinoides may serve as a source of potent antioxidants that may be used in the prevention of various diseases such as cancer,diabetes and cardiovascular diseases due to the presence of phenolic compounds.HPTLC finger print of Evolvulus alsinoides may be useful in the differentiation of the species from adulterants and act as a biochemical marker for this medicinally important plant in the pharmaceutical industry and plant systematic studies.

Electron beam welding of Ti-15-3 titanium alloy to 304 stainless steel with copper interlayer sheet

Electron beam welding of Ti-15-3 titanium alloy to 304 stainless steel with a copper sheet as interlayer was carried out.Microstructures of the joint were studied by optical microscopy(OM),scanning electron microscopy(SEM) and X-ray diffractometry(XRD).In addition,the mechanical properties of the joint were evaluated by tensile test and the microhardness was measured.These two alloys were successfully welded by adding copper transition layer into the weld.Solid solution with a certain thickness was located at the interfaces between weld and base metal in both sides.Regions inside the weld and near the stainless steel were characterized by solid solution of copper with TiFe2 intermetallics dispersedly distributed in it.While weld near titanium alloy contained Ti-Cu and Ti-Fe-Cu intermetallics layer,in which the hardness of weld came to the highest value.Brittle fracture occurred in the intermetallics layer when the joint was stretched.

Optimizing the nickel boride layer thickness in a spectroelectrochemical ATR-FTIR thin-film flow cell applied in glycerol oxidation

The influence of the drop-casted nickel boride catalyst loading on glassy carbon electrodes was investigated in a spectroelectrochemical ATR-FTIR thin-film flow cell applied in alkaline glycerol electrooxidation.The continuously operated radial flow cell consisted of a borehole electrode positioned 50μm above an internal reflection element enabling operando FTIR spectroscopy.It is identified as a suitable tool for facile and reproducible screening of electrocatalysts under well-defined conditions,additionally providing access to the selectivities in complex reaction networks such as glycerol oxidation.The fast product identification by ATR-IR spectroscopy was validated by the more time-consuming quantitative HPLC analysis of the pumped electrolyte.High degrees of glycerol conversion were achieved under the applied laminar flow conditions using 0.1 M glycerol and 1 M KOH in water and a flow rate of 5μL min^(–1).Conversion and selectivity were found to depend on the catalyst loading,which determined the catalyst layer thickness and roughness.The highest loading of 210μg cm^(–2)resulted in 73%conversion and a higher formate selectivity of almost 80%,which is ascribed to longer residence times in rougher films favoring readsorption and C–C bond scission.The lowest loading of 13μg cm^(–2)was sufficient to reach 63%conversion,a lower formate selectivity of 60%,and,correspondingly,higher selectivities of C_(2)species such as glycolate amounting to 8%.Thus,only low catalyst loadings resulting in very thin films in the fewμm thickness range are suitable for reliable catalyst screening.

Extraction of essential oil from shaddock peel and analysis of its components by gas chromatography-mass spectrometry

Essential oil, with more than thirty kinds of compounds separated and identified by gas chromatography-mass spectrometry, was extracted from Shatian shaddock peel and Sweet shaddock peel by squeeze-steam distillation and direct steam distillation method. Among their composition, the main components are terpene compounds, which account for 93.926% (mass fraction, the same below) and 85.843% of essential oils extracted from Shatian shaddock peel and Sweet shaddock peel, respectively. Although nootkatone is the major contributor of shaddock characteristic scent, and its contents are 1.069% and 1.749% of essential oils from Sweet shaddock peel and Shatian shaddock peel, respectively. The results show that squeeze-steam distillation gives higher yield and good quality of essential oil and the compositions of essential oils from two kinds of shaddock peels are different, but the main contributors of the shaddock scent are the same.

Layer regrouping for water-flooded commingled reservoirs at a high water-cut stage

Layer regrouping is to divide all the layers into several sets of production series according to the physical properties and recovery percent of layers at high water-cut stage, which is an important technique to improve oil recovery for high water-cut multilayered reservoirs. Dif- ferent regroup scenarios may lead to different production performances. Based on unstable oil-water flow theory, a multilayer commingled reservoir simulator is established by modifying the production split method. Taking into account the differences of layer properties, including per- meability, oil viscosity, and remaining oil saturation, the pseudo flow resistance contrast is proposed to serve as a characteristic index of layer regrouping for high water-cut multilayered reservoirs. The production indices of multi- layered reservoirs with different pseudo flow resistances are predicted with the established model in which the data are taken from the Shengtuo Oilfield. Simulation results show that the pseudo flow resistance contrast should be less than 4 when the layer regrouping is implemented. The K-means clustering method, which is based on the objec- tive function, is used to automatically carry out the layer regrouping process according to pseudo flow resistances. The research result is applied to the IV-VI sand groups of the second member of the Shahejie Formation in the Shengtuo Oilfield, a favorable development performance is obtained, and the oil recovery is enhanced by 6.08 %.

Evaluation of quantitative variation of secondary metabolites in Bergenia ciliata(Haw.)using high performance thin layer chromatography

Dear Editor： Therapeutically active metabolite contents in a med- icinal plant vary in nature, which may impact on its therapeutic efficacy. Bergenia （Saxifragaceae） is an evergreen perennial herb widely distributed in Central and East Asia with about 30 species reported worldwide. It grows at a range of altitudes from the Khasia hills at 400 feet to the temperate Himalayas from Kashmir to Bhutan at 7,000-10,000 feet. Its distribution over a wide range of altitudinal zones makes it a good candidate for studying variations in its metabolic profiles under different climatic conditions. Bergenin （C-glycoside of 4-O-methyl gallic acid） has been identified as a potent active secondary metabolite in Bergenia and other therapeutically active constituents including, among others, gallic acid （3,4,5 trihydroxybenzoic acid）, （＋） catechin, and gallicin （Fig. 1）.

基于ML-PCA-BP模型的多环芳烃拉曼光谱定量分析

芘作为多环芳烃(PAHs)类物质广泛存在于自然环境中,亲脂性强,对人体有致癌影响。因此,食用油中芘的含量的判定对品质的把控具有深远的意义。采用拉曼光谱与人工智能算法相结合进行多环芳烃的定量分析是当前的一个研究热点。将一毫升食用油与不同固定浓度的芘液体混合制作样本,然后制作薄层色谱板与金粒子,采用薄层色谱和表面增强拉曼散射(SERS)光谱相结合的方法进行实验获得光谱数据,选取自适应迭代加权惩罚最小二乘算法进行预处理,再采用Multi parameter-Principal Component Analysis-Back Propagation Neural Network模型方法进行定量分析。该模型首先在预处理后的光谱中选取两个特征峰进行分峰拟合获取特征峰的高度、半高宽、面积等参数。将两个特征峰的拉曼数据与通过拟合获取的参数进行归一化再采用主成分分析获取关键参数,将获取的关键参数作为输入层输入基于L2正则化的BP神经网络中,输出预测浓度。实验分别采用不同的算法进行浓度预测,实验结果表明,通过偏最小二乘算法预测的芘浓度,其测试集决定系数R^(2)为0.58,均方根误差(RMSEC)为1.85;采用线性回归拟合特征峰面积与浓度的规律最终预测的芘浓度,其测试集决定系数R^(2)为0.26,均方根误差(RMSEC)为2.28;采用Multi parameter-Principal Component Analysis-Back Propagation Neural Network模型预测芘浓度,其测试集决定系数R^(2)为0.99,均方根误差(RMSEC)为0.31,Multi parameter-Principal Component Analysis-Back Propagation Neural Network模型预测精准度更高,误差更小。模型是针对光谱数据信息与样本浓度之间非线性、高维度的关系,而建立的预测精度及建模效率均高于同类对比的算法模型。模型拟合特征峰获取关键变量,将关键变量与特征峰的拉曼位移都作为特征向量,因此特征向量较为充分,模型利用PCA提取拉曼光谱非线性特征并且采用基于L2正则化BP神经网络泛化力强的优点,防止过拟合,因此可以更加精准快捷地预测出芘的浓度。