Current Articles

2022, Volume 28,  Issue 3

Morphological Characterization of Poly(N-Isopropylmethacrylamide)@Poly(N-Isopropylacrylamide) Hollow Microgel Synthesis Process
GUO Hong-bo, BAI Lu, HU Xi-xue, SUN Di
2022, 28(3): 233-240. doi: 10.16495/j.1006-3757.2022.03.001
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The synthesis process of poly(N-isopropylmethacrylamide)@poly(N-isopropylacrylamide) (PNIPMAM@PNIPAM) hollow microgels has been studied. Using the morphological characterization method combined with scanning electron microscopy (SEM) and transmission electron microscopy (TEM), the particle size, three-dimensional and internal ultrastructure of core-shell microgels in a simple and intuitive way can be obtained. Furthermore, the morphological characteristics of the synthesis process of PNIPMAM@PNIPAM hollow concentric double-shell microgels were revealed.
Study on Denaturation and Damage of Deoxyribonucleic Acid in Liquid Phase Using Atomic Force Microscopy
LUO Yun-er, GAO Shan, YI Yi, LU Yi, ZHENG Yu, WANG Yan-wei, PAN Hai-ou
2022, 28(3): 241-246. doi: 10.16495/j.1006-3757.2022.03.002
Abstract(14) HTML (5) PDF(1)
The denaturation and damage of deoxyribonucleic acid (DNA) greatly hinders the replication and transcription of DNA, so the study on the mechanism of DNA damage and denaturation in the physiological environment is benefited to the study of its physical and chemical properties, which is of great significance to the gene therapy. Firstly, using the atomic force microscopy (AFM) to compare DNA in gas and liquid environments, it was found that the DNA images obtained in the liquid environment were clearer than those in the gas phase, and the DNA in the liquid phase was more flexible and relaxed. Secondly, the effect of dimethyl sulfoxide (DMSO) and peroxynitrite (PN) on the morphology of DNA was studied in the liquid phase. It was found that with the increase of the concentration of DMSO, the denatured degree of DNA was enhanced, and the circular DNA molecule changed from an unwound structure to an overlapping helix structure. At the same time, with the increase of the concentration of PN, linear DNA changed from a naturally stretched state to a more bent one, and broke into shorter DNA fragments. Finally, the model diagram was used to explain that DMSO and PN changed the structure of DNA, and damage and degeneration occurred after the structure of DNA became unstable.
Zhejiang Major Scientific Research Instruments Open and Shared Platform-Column on Electron Microscopy
Characterization of Microstructure of Deformation Twin Boundary in Zinc by Transmission Electron Microscopy
WU Hai-chen, CHEN Guo-xin, YU Hai-tao, SHEN Sheng-cheng, LIANG Rui, LU Huan-ming
2022, 28(3): 247-253. doi: 10.16495/j.1006-3757.2022.03.003
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The microstructure of {$10{\bar 1}2 $} twin boundary in zinc induced by severe plastic deformation was characterized using transmission electron microscope (TEM). The result showed that the actual twin boundary can deviate significantly from the theoretical twinning plane. By high resolution TEM analysis, the actual twin boundaries consist of ($10{\bar 1}2 $) coherent twin boundary (CTB) connected with short BP/PB facets, or only consist of a series of BP/PB facets perpendicular to each other. These two kinds of twin boundaries with different microstructures can coexist stably in a {$10{\bar 1}2 $} twin. Based on the dislocation theory, the migration mechanism of these two kinds of twin boundaries was discussed. For the first kind of twin boundary, the migration can be accomplished via the motion of twinning dislocation on the CTB together with the motion of interface dislocation on the BP/PB facets. For the second kind of twin boundary, the migration is accomplished via a unit cell reconstruction mechanism. The coexistence of the two kinds of twin boundaries can be explained based on the nucleation and growth process of a {$10{\bar 1}2 $} twin.
Analysis of High-Performance Thermoplastic Plates Based on Scanning Electron Microscopy and Energy Dispersive Spectrometry
ZHENG Na, XU Li, SHEN Su-dan, HE Jing, FANG Er-yuan, PU Qun, JIE Su-yun
2022, 28(3): 254-259. doi: 10.16495/j.1006-3757.2022.03.004
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High-performance thermoplastic plates are widely used in automobiles, electrical appliances, medicine, building materials and so on. Some functional elements, such as Ti and Sb, are often added to improve their performance. How to detect its composition and contents quickly is very important for the study of thermoplastic plates. The morphology and composition of high-performance thermoplastic plates has been analyzed by scanning electron microscopy and energy dispersive spectrometry (SEM/EDS), the effects of conductive treatment on the morphology and composition have been studied respectively. The thermodynamic characteristics of high-performance thermoplastic plates were analyzed by the thermal analysis technology. The results showed that the high-performance thermoplastic plate without a conductive treatment was decomposed and sublimated during the EDS analysis, and the functional elements disappeared, so its composition and content cannot be accurately detected. A proper conductive treatment in the EDS analysis of high-performance thermoplastic plate provides a method and guidance for its accurate detection.
Application of Scanning Electron Microscopy-Energy Dispersive Spectroscopy in Identification of Pharmaceutical Packaging Materials
CAI Zhi-wei, LIANG Jian-mou, CHEN Chao
2022, 28(3): 260-266. doi: 10.16495/j.1006-3757.2022.03.005
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A new identification method for pharmaceutical packaging materials has been developed based on the scanning electron microscope-energy dispersive spectroscope (SEM-EDS). SEM-EDS combined with infrared spectrophotometer and differential scanning calorimeter to analyze and identify the rubber stopper and laminated film of unknown composition, and the thickness was measured. The rubber stopper was a brominated butyl rubber stopper covered by ethylene-tetra-fluoro-ethylene with a thickness of about 24 μm, and the laminated film was a polyethylene terephthalate/low density polyethylene/aluminum/low density polyethylene laminated film with a thickness of about 38, 19, 13 and 14 μm, respectively. The SEM-EDS identification method for pharmaceutical packaging materials can determine the elemental composition and proportion of unknown compounds, thus solves the bottleneck encountered by the traditional identification, improves the efficiency and accuracy of identification greatly, and provides new ways for identifying pharmaceutical packaging materials.
Fracture Analysis of Piston Rod for New Hydrogen Compressor
YAO Yi-rong, JIANG Rong-rong, DUAN Bei-chen, GUAN Jian-min, XIONG Fa-hao, LI Ming, LU Huan-ming
2022, 28(3): 267-272. doi: 10.16495/j.1006-3757.2022.03.006
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Optical microscope (OM), scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and spark discharge atomic emission spectrometer were used to analyze the fracture reason of the piston rod for a new hydrogen compressor. The results manifested that the chemical composition and metallographic structure of 42CrMo steel accorded with the standards. The failure of piston rod was caused by the fracture fatigue. A large number of alumina inclusions, sharp and aggregated, with the size largerer than 10 μm, were present within the piston rod. Under the action of alternating loads, stress concentration was formed where these inclusions were gathered, and fatigue cracks were formed. This is the main reason for the fracture of the piston rod.
Application of Scanning Electron Microscopy in Quail Eggshell Characterization
ZHENG Xi, RONG Nian-hang
2022, 28(3): 273-279. doi: 10.16495/j.1006-3757.2022.03.007
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The microstructure of the outer surface and cross section of quail eggshell has been observed using a scanning electron microscope (SEM). The results showed that the quail eggshell was composed of shell membrane, mastoid layer, sponge layer, vertical crystal layer and stratum corneum from inside to outside. The outer surface was distributed with dark brown and light yellow irregular color spots. The stratum corneum in the dark brown area was thicker than that in the light yellow area. The difference comes from the stratum corneum. The energy spectrum results showed that the contents of C, O and N in the dark brown area were relatively higher than those in the light yellow area, and the contents of Mg, P, S and Ca in the light yellow area were relatively higher than those in the dark brown area.
Scanning Transmission Electron Microscopy and Its Application in Traditional Chinese Medicine Research
WANG Yue-xia
2022, 28(3): 280-288. doi: 10.16495/j.1006-3757.2022.03.008
Abstract(11) HTML (3) PDF(0)
Scanning transmission electron microscopy (STEM), a necessary tool for the microstructure of materials and microarea analysis, combines the advantages of transmission electron microscopy (TEM) and scanning electron microscopy (SEM), and has the advantages of high-resolution imaging, strong atomic contrast sensitivity, and easy-to-understand visual images. Traditional Chinese medicine research has a long history. Microscopic technology has always been one of the important means to study the micro-characteristics and mechanism of medicinal materials, and is irreplaceable to the other technologies. The principles, methods and technical characteristics of STEM, as well as its application in the microstructure and nanoparticles of traditional Chinese medicine has been reviewed, in order to provide reference for the further expansion of the research on the micro-characteristics of traditional Chinese medicine.
Practice and Exploration on Operation and Management of Scanning Electron Microscope
HE Yi-chao, SHENG Guo-dong, CHEN Chao-gui, WANG Lin-xia
2022, 28(3): 289-292. doi: 10.16495/j.1006-3757.2022.03.009
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The scanning electron microscope (SEM) is an indispensable instrument for analyzing the internal structure and chemical composition of samples in the modern material field. SEM has been installed and running for more than 10 years in Shaoxing University and the effective testing time is over 1000 hours per year, SEM is one of the instruments with the highest utilization rate in the school. Combined with the experience in the management and operation of large-scale instruments and some existing problems, the future management system of the instrument from the technology improvement, instrument sharing, evaluation system, etc., were discussed.
New Method
Determination of Gallium Ions Released from New Antibacterial Stainless Steel in Normal Saline and Phosphate Buffered Solution by Inductively Coupled Plasma Mass Spectrometry
YU Ying-jie, LI Hui, ZHANG Zhong-yuan
2022, 28(3): 293-298. doi: 10.16495/j.1006-3757.2022.03.010
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A method for the determination of gallium ions released from new antibacterial stainless steel in normal saline and phosphate buffered solution (PBS) by inductively coupled plasma mass spectrometry has been established. To eliminate the effect of salt deposition, a Burgerner AriMist high-salt-resistant nebulizer and a thickened skimmer cone insert were employed in the present sample system. In the meantime, the matrix effect was corrected by diluting the sample and using indium as the internal standard. Under the selected analysis conditions, the linear correlation coefficient of the calibration curve was greater than 0.999, the detection limit was 0.08 μg/L, the relative standard deviations of determination results was less than 3.0% (n=6) and the recoveries were between 98.3% and 105.4%. The method is simple and fast, and suitable for the rapid determination of trace gallium in normal saline and PBS.
Determination of Stearic Acid and Palmitic Acid in Medical Rubber Plug Extracting Solution by Non-derivative Gas Chromatography
YU Qiu-ling, MA Yan, XIE Wei, YANG Qian, LONG Mei
2022, 28(3): 299-303. doi: 10.16495/j.1006-3757.2022.03.011
Abstract(7) HTML (1) PDF(1)
A non-derivative gas chromatography (GC) for determining stearic acid and palmitic acid in the extracting solution of medical rubber plug has been established. Three different media (pH=3 acidic buffer solution, pH=10 alkaline buffer solution, 20% ethanol solution) were used to extract the rubber plug. The extracted solution was extracted by hexane, separated on a DB-FFAP (30 m×0.25 mm×0.25 μm) column, detected by a flame ionization detector (FID), and quantified by an external standard method. The results showed that the peaks of stearic acid and palmitic acid were symmetrical under optimal conditions. The separation effect was good and the linear curve fitted well. The average recoveries were 97.6%~100.5%, and the relative standard deviations (RSD) were 0.4%~2.3% (n=6). The detection limit (LOD) was 1.0 mg/L to 1.5 mg/L. The method is simple and accurate, and can be used for the determination of stearic acid and palmitic acid in the extracting solution of medicinal rubber plug.
Determination of Trace Br and SO4 2− in Potassium Chloride by Ion Chromatography
JIN Zhen, YAN Chun-hui
2022, 28(3): 304-307. doi: 10.16495/j.1006-3757.2022.03.012
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A method for rapid detection of trace bromide and sulfate ions in potassium chloride by ion chromatography with suppressed conductivity has been established. The calibration curves of Br and SO4 2− showed good linearity in the range of 0.05~10 mg/L (r was 0.995 1, 0.996 2, respectively). The detection limits of Br and SO4 2− were 0.029 mg/L and 0.020 mg/L, respectively. The recoveries of Br and SO4 2− in potassium chloride ranged from 93.7% to 99.0%. The method is of a good linear range, easy operation and high sensitivity, can be used as the quality control method for the rapid detection of Br and SO4 2− in potassium chloride.
Troubleshoot Maintenance
Troubleshooting and Cause Analysis of Graphite Furnace Atomization Method for Atomic Absorption Spectrophotometer
YU Zheng-jun, YIN Xiao-hong, LI Hai-lin, YANG Liu, BI Jing-xiu, FU Zhi-qiang
2022, 28(3): 308-311. doi: 10.16495/j.1006-3757.2022.03.013
Abstract(8) HTML (1) PDF(1)
Taking PinAAcle 900T atomic absorption spectrophotometer (AAS) as the research object, the common faults in the graphite furnace atomization method were diagnosed, and the corresponding solutions were put forward.
Analysis of Domestic Patent Status of Spectroscopic Water Quality Monitoring Instruments and Methods
CHANG Xi-feng, YU Gong-liang, HAN Lu-lu, WANG Tao, SHI An-qi, QIAO Zhi-yi
2022, 28(3): 312-319. doi: 10.16495/j.1006-3757.2022.03.014
Abstract(7) HTML (2) PDF(1)
Water quality dynamic data can provide data support for the sustainable development of water environment, and the development of water quality monitoring instruments and methods is the key to obtain accurate water quality data and formulate pollution prevention and control planning. At present, the development direction of patents related to spectroscopic water quality monitoring instruments and methods is not clear. Based on the patent database of Wanfang Data knowledge service platform, the patent data of spectroscopic water quality monitoring instruments and methods applied in China from 1993 to 2022 were retrieved, and the patent application status, instrument types involved in the patented instruments and methods, subject of patent applications and their distribution areas, etc. were compared and analyzed. Through the comparative study, the development trend of domestic spectroscopic water quality monitoring instruments and methods were revealed, in order to provide a decision-making basis for the relevant personnel of the government, scientific research institutions and enterprises to develop spectroscopic water quality monitoring instruments and methods.
Research Hotspots and Trends of Laboratory Science Technicians Based on CiteSpace
Yue Qi, WANG Jin
2022, 28(3): 320-326. doi: 10.16495/j.1006-3757.2022.03.015
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Bibliometrics and knowledge maps are used to analyze the research hotspots of the laboratory science technicians, and CiteSpace software is used to analyze the authors, units, journals, keywords and other information of related articles, and to study the hotspots and changing trends of the experimental technical team. The research showed that the number of related studies is on the rise as a whole, there are many research units and scholars in this field across the country, but there is a lack of authoritative core research teams. In recent years, keywords such as "scientific research instruments", "open sharing", and "performance assessment" have replaced keywords such as "laboratory", "management system", and "experimental teaching" as new research hotspots. The laboratory science technicians are inseparable from "scientific research instruments" and "open sharing", compared with the growth of scientific research instruments, there are still problems of insufficient quantity and poor quality of experimental teams.
Exchange Maintenance
Effect of Gas Chromatographic Column on Analysis of Polybrominated Diphenyl Ethers
ZHANG Wei, FENG Hao, ZHANG Bing, YANG Yong-tan
2022, 28(3): 327-333. doi: 10.16495/j.1006-3757.2022.03.016
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11 representative polybrominated diphenyl ethers (PBDEs) were analyzed based on the gas chromatography-electron capture detector method, and the effects of different types of gas chromatographic columns on the separation and analysis of PBDEs were investigated. The results showed that the polarity of column is the key factor affecting the separation and response. On the stationary phase with stronger polarity, the retention time of each PBDEs monomer became longer and the response decreased, especially the response of highly substituted PBDEs was most affected. The column length and thickness stationary phase also have significant effects on the PBDEs analysis. Short column with thin stationary phase were suitable for the analysis of 11 PBDEs. Different brands of columns were affected by the production process and have a greater effect on the response to PBDEs.
Measurement of CO2 Response Curve Based on CIRAS-3 Photosynthesizer
RAO Xin-yu, YANG Cui-zhen, LI Yong-ping, LI Zi-wen, SONG Zhi-jiao
2022, 28(3): 334-342. doi: 10.16495/j.1006-3757.2022.03.017
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CIRAS-3 portable photosynthetic apparatus, as a precision instrument for measuring plant photosynthesis, plays an important role in the study of plant photosynthesis, transpiration, respiration and chlorophyll fluorescence. However, in the process of use, due to many precautions and improper operation, the experimental data error is large. In order to help the beginners to master the method of measuring CO2 response curve of plants quickly using a CIRAS-3 photosynthesizer, and obtain more accurate test data, according to our experience, the operation steps and precautions of the measurement of CO2 response curve were described in detail. In order to provide a certain reference for the beginners, so as to improve the efficiency of the photosynthesizer.
Study on Mechanism of Volatile Oil from Papaver Somniferum sp. Hydbr. Ziban for Anti-cough, Expectorant, and Asthma by Gas Chromatography-Mass Spectrometry and Network Pharmacology
SONG Xiao-lan, WANG Li-ping, ZHAO Ning-juan, LI Jian-hui, YANG Lu, WANG Nuo, KANG Wen-li, WANG Xiao-zhong, ZHANG Wei, WU Quan-xiang
2022, 28(3): 343-352. doi: 10.16495/j.1006-3757.2022.03.018
Abstract(10) HTML (1) PDF(3)
In order to study the components and mechanism of volatile oil from Papaver somniferum sp. hydbr. Ziban for anti-cough, expectorant, and asthma, the components of volatile oil from Papaver somniferum sp. hydbr. Ziban has been analyzed by the gas chromatography-mass spectrometry (GC-MS), and the active ingredient targets have been screened by Pubchem and Swiss Target Prediction database. The disease targets related to anti-cough, expectorant, and asthma were searched in the GeneCards database. The intersection genes were extracted by the online Venn. The component-target-disease network graph was built using a Cytoscap 3.7.1 software to screen the key components. The protein interaction network was constructed by a String database to screen the core targets. The enrichment analysis of Gene ontology (GO) function and Kyoto encyclopedia of genes and genomes (KEGG) pathway was achieved by the DAVID database. The results showed that twenty-eight chemical components were identified by GC-MS, and 259 targets corresponding to 20 active components were obtained by the virtual screening. Through the network pharmacology the essential oil of Papaver somniferum sp. hydbr. Ziban plays a therapeutic role for anti-cough, expectorant, and asthma through the key targets such as tumor necrosis factor (TNF), serine/threonine-protein kinase (AKT1), tyrosine-protein kinase (SRC), epidermal growth factor receptor (EGFR) and MAP kinase 1 (MAPK1), and then synergistically regulates tumor pathways, neural ligand-receptor interaction, PI3K-Akt signaling pathway and other pathways is predicted. The study provides a reference and guidance for the further study on the mechanism and the volatile oil from Papaver somniferum sp. hydbr. Ziban in the treatment of disease of respiratory system.
Determination of 12 Index Components and Illegally Added Components in Compound Danshen Tablets by High Performance Liquid Chromatography-Diode Array Detector
FAN Ke-qing, LING Xia
2022, 28(3): 353-357. doi: 10.16495/j.1006-3757.2022.03.019
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An analysis method has been established for the determination of 12 components in compound Danshen tablets by high performance liquid chromatography-diode array detector, and it was determined whether there were illegally mixed Panax notoginseng leaves in compound Danshen tablets. The mobile phase was acetonitrile-0.1% aqueous phosphate solution (gradient elution). The sodium Danshensu, protocatechuic acid, protocatechualdehyde, rosmarinic acid, salvianolic acid B, notoginsenoside R1, ginsenoside Rg1, ginsenoside Re, ginsenoside Rb1, ginsenoside Rb3, tanshinone I, tanshinone IIA were analyzed by changing the wavelengthes and UV spectral scanning qualitative method. The linear relationship of the 12 components was good (r≥0.999 2), and the precision (RSD<2.0%), stability (RSD<2.0%) and recovery rate (96.1%~99.8%) all met the methodological requirements, which can be used for the quality control of compound Danshen tablets.
Determination of Metal Elements in Aluminum Alloy by Inductively Coupled Plasma Emission Spectrometry
SUN Yong-fang
2022, 28(3): 358-362. doi: 10.16495/j.1006-3757.2022.03.020
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By dissolving aluminum alloy samples with hydrochloric acid-nitric acid-hydrofluoric acid, six elements of silicon, manganese, copper, iron, magnesium and zinc in aluminum alloy were determined by inductively coupled plasma emission spectrometry. The analytical spectral lines with high sensitivity, low interference and high response intensity were selected, and the recovery rate and precision of aluminum alloy samples were tested by the matrix matching method. The sample tests were carried out for aluminum alloy samples with silicon mass fraction of 0.05%~10.00%. The results showed that the recoveries of six elements in aluminum alloy were 93.0%~109.3%, and the relative standard deviations (RSD) were 0.35%~3.14%, and the accuracy and repeatability were good, which can meet the daily inspection requirements.