Zastita materijala最新文献_第7页

Elementary particle microstates in sandwich nanostructures 三明治纳米结构中的基本粒子微观态

Zastita materijala Pub Date : 2023-01-01 DOI: 10.5937/zasmat2302198s

J. Šetrajčić, S. Vučenović, S. Jaćimovski

引用次数: 0

Analysis of the causes of fracture of the main gas pipeline 输气干线断裂原因分析

Zastita materijala Pub Date : 2023-01-01 DOI: 10.5937/zasmat2302177n

L. Nyrkova, Anatolii Rybakov, L. Goncharenko, S. Osadchuk, Yulia Kharchenko

{"title":"Analysis of the causes of fracture of the main gas pipeline","authors":"L. Nyrkova, Anatolii Rybakov, L. Goncharenko, S. Osadchuk, Yulia Kharchenko","doi":"10.5937/zasmat2302177n","DOIUrl":"https://doi.org/10.5937/zasmat2302177n","url":null,"abstract":"A complex of research has been conducted to establish the causes of the accident of the main gas pipeline made of 1420x15.7 mm X70 steel after 20 years of operation. It is found that pipe destruction was initiated by the longitudinal crack with a length of 470 mm and a maximum depth of 6.8 mm, oriented in the direction of the pipe and perpendicular to the outer surface of the pipe identified as stress-corrosion cracking. The crack initiation is due to the disboundment of the tape protection coating, the high corrosion activity of the soil, and the complex stress-strain state caused by deviations from the design objectives during construction. The chemical composition the base metal of all investigated pipes corresponds to the requirements of the technical conditions for steel pipes in category X70; pipes welding are performed with the typical materials used in pipe welding plants. Despite the differences, the structural and mechanical characteristics (yield strength, ultimate strength, and impact strength) of the steel and weld metal of the studied pipes are identical. The relative elongation (d5) of the operated pipes is below the normalized values, but, it is necessary to take into account the possibility of deviations in these characteristics of steel in the initial state. Significant reserves of toughness indirectly indicate low damage of metal and, accordingly, satisfactory resistance to destruction of the metal of the studied pipes.","PeriodicalId":23842,"journal":{"name":"Zastita materijala","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79708267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Investigating the therapeutic effect of folic acid conjugated ZnO nanoparticles on human triple negative breast cancer cell line 研究叶酸共轭ZnO纳米颗粒对人三阴性乳腺癌细胞株的治疗作用

Zastita materijala Pub Date : 2023-01-01 DOI: 10.5937/zasmat2302213s

Shiva Sabzandam, Masoumeh Zahmatkeshan, Moein Adel, Mehrad Mehrdadian, Farzaneh Saliminia, F. Esmaeili

{"title":"Investigating the therapeutic effect of folic acid conjugated ZnO nanoparticles on human triple negative breast cancer cell line","authors":"Shiva Sabzandam, Masoumeh Zahmatkeshan, Moein Adel, Mehrad Mehrdadian, Farzaneh Saliminia, F. Esmaeili","doi":"10.5937/zasmat2302213s","DOIUrl":"https://doi.org/10.5937/zasmat2302213s","url":null,"abstract":"Triple-negative breast cancer (TNBC) accounts for 15-20% of all invasive breast cancers and has a poor prognosis. ZnO NPs are promising anti-cancer agents. Moreover, folate Alpha receptor (FRa) is a potential biomarker and therapeutic target because it is significantly expressed in TNBC. Therefore, ZnO and folic acid-conjugated ZnO (F-ZnO) NPs were synthesized by the solgel method. NPs were characterized by DLS, zeta potential, TEM, FTIR, and ICP-MS. FA-ZnO NPs had a mean diameter of 20 ± 2 nm and a surface charge of -15 mV, while ZnO NPs had a mean diameter of 40 ± 5 nm and a surface charge of -5 mV. The MTT assay and trypan blue test, respectively, were used to determine the cytotoxicity and viability percentage of ZnO and F-ZnO NPs at different concentrations of 2, 4, 8, 16, 32, 64 and 128 µg/mL for 12, 24, 48 and 72 hours (h) on the human TNBC cell line MDA-MB-231. The results indicated that both ZnO and F-ZnO NPs significantly reduced the viability of the cancer cells in a dose-dependent and time-dependent manner (p<0.05). The IC50 values for FA-ZnO NPs were approximately 3, 3.74, 4.38 and 5.5 times higher than those for ZnO NPs at 12-, 24-, 48and 72-hour time points, respectively. The results suggest that F-ZnO NPs have the potential to be a good option for TNBC treatment and warrant further investigations.","PeriodicalId":23842,"journal":{"name":"Zastita materijala","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80417976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effects of Desulfotomaculum sp on corrosion behaviour of mild steel and aluminium in sea water 脱硫剂对低碳钢和铝在海水中腐蚀行为的影响

Zastita materijala Pub Date : 2023-01-01 DOI: 10.5937/zasmat2302190i

E. Imo, C. Ihejirika, Adaugo Ndukaku, Peter Misoni

引用次数: 0

The inhibition of mild steel corrosion by papaya and neem extracts 木瓜和楝树提取物对低碳钢的缓蚀作用

Zastita materijala Pub Date : 2023-01-01 DOI: 10.5937/zasmat2303274n

A. Ndukwe, Dan Etim, Anaele Uchenna, Ozoh Chibuike, Kooffreh Okon, Paulinus Agu

{"title":"The inhibition of mild steel corrosion by papaya and neem extracts","authors":"A. Ndukwe, Dan Etim, Anaele Uchenna, Ozoh Chibuike, Kooffreh Okon, Paulinus Agu","doi":"10.5937/zasmat2303274n","DOIUrl":"https://doi.org/10.5937/zasmat2303274n","url":null,"abstract":"This study examined earlier research on using papaya and neem extracts as inhibitors to minimize the corrosion of mild steel in a variety of corrosive situations. The potential inhibitory characteristics of plant extracts to potentially replace the hitherto used, well-known inhibitors that are harmful to the people handling them as well as the environment, inspired several scholars to conduct corrosion inhibition tests on metals using plant extracts. The findings of earlier research demonstrated that the maximal inhibitory efficiency provided by neem leaf extract to prevent the degradation of carbon steel in a hydrochloric acid (1 M) medium was 97%, while 86% was observed for the protection in H2SO4 (1 M) solution. The extract from Carica papaya leaves was shown to have up to 83% maximum inhibitory efficacy for preventing mild steel corrosion in HCl (1 M). It has been revealed that when extract concentration increased, the rate of steel corrosion reduced. Additionally, papaya leaves' corrosion-inhibiting mechanism was said to occur mostly in the cathodic area. Both plant-leaf extracts (Papaya and Neem) have been reported to have adsorption qualities that, for the most part, agreed with the Langmuir adsorption isotherm model.","PeriodicalId":23842,"journal":{"name":"Zastita materijala","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85995766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The inhibitive effect of magnetic fields on mild steel corrosion in acidic media 磁场对酸性介质中低碳钢腐蚀的抑制作用

Zastita materijala Pub Date : 2023-01-01 DOI: 10.5937/zasmat2301030o

Obi Tamadu, Mejeha Maurice, Okeoma Bierechi

{"title":"The inhibitive effect of magnetic fields on mild steel corrosion in acidic media","authors":"Obi Tamadu, Mejeha Maurice, Okeoma Bierechi","doi":"10.5937/zasmat2301030o","DOIUrl":"https://doi.org/10.5937/zasmat2301030o","url":null,"abstract":"The inhibitive effect of applied magnetic fields on the corrosion of mild steel in 1.0M HCl and 0.5M H2SO4 acid solutions has been investigated at room temperature by using the gravimetric technique. A locally made electromagnet with variable outputs and powered by a direct current source voltage provided the magnetic fields. In a typical experiment, the applied magnetic field was applied perpendicularly onto the surface of a mild steel coupon immersed completely in a chosen acid solution for an exposure time of two hours. It was observed that the corrosion rates of mild steel determined for each case of 1.0M HCl and 0.5M H2SO4 test solutions decrease as the applied magnetic field increases. This indicates that the presence of the applied magnetic field inhibits the corrosion of the mild steel in the test solutions. Results also show that the protection efficiency of the magnetic field increases as the applied magnetic field increases. More specifically, as the magnetic field was increased from 118.2 - 764.3mG [or 0.01182 - 0.07643 mT], the protection efficiency increased from 36.34 - 62.67% for mild steel in 1.0M HCl acid solution, while for mild steel in 0.5M H2SO4 acid solution, the protection efficiency increased from 12.68 - 46.88%. It was demonstrated that the observed inhibitive effect of the magnetic fields can be attributed partly to the phenomenon of transverse magnetoresistance and partly to the effect of the magnetic fields on the mass transport properties of the constituent ions in the electrochemical system","PeriodicalId":23842,"journal":{"name":"Zastita materijala","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87258052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Electrochemical studies on the corrosion resistance of Gold 18K and thermo active alloy in artificial sweat in presence of sodium chloride 氯化钠存在下金18K和热活性合金在人工汗液中的耐蚀性电化学研究

Zastita materijala Pub Date : 2023-01-01 DOI: 10.5937/zasmat2301038g

T. Gowrani, Nilavan Anitha, M. Dhanalakshmi, Subramaniam Aishwarya, Mary Subashini, Jenifer Flori, Shree Nithiya, Gurmeet Singh, A. Al-Hashem, S. Rajendran

{"title":"Electrochemical studies on the corrosion resistance of Gold 18K and thermo active alloy in artificial sweat in presence of sodium chloride","authors":"T. Gowrani, Nilavan Anitha, M. Dhanalakshmi, Subramaniam Aishwarya, Mary Subashini, Jenifer Flori, Shree Nithiya, Gurmeet Singh, A. Al-Hashem, S. Rajendran","doi":"10.5937/zasmat2301038g","DOIUrl":"https://doi.org/10.5937/zasmat2301038g","url":null,"abstract":"Corrosion resistance of thermo active alloy and Gold 18K alloy immersed in artificial sweat in the absence and presence of 100 ppm of NaCl has been investigated by polarization study and AC impedance spectra. It is observed that corrosion resistance of thermo active alloy and also Gold 18K alloy immersed in artificial sweat in the presence of 100 ppm of NaCl increases. Hence it is concluded that people wearing ornaments made of these two alloys need not worry about the excess of sodium chloride in their sweat. When thermo active alloy is immersed in artificial sweat in the presence of 100 ppm of NaCl, linear polarization resistance value increases from 1760283 Ohm cm2 to 9506106 Ohm cm2 ; corrosion current decreases from 1.845x10-8 to 4.008x10-9 A/cm2 ; charge transfer resistance value increases from 4884 Ohmcm2 to 12210 Ohm cm2 ; impedance value increases from 4.367 to 4.8; double layer capacitance decreases from 1.0442 x10 -9 to 4.1769x10-10 F/cm2 , and phase angle increases from 48.1 to 66.34°. When Gold 18K alloy is immersed in artificial sweat in the presence of 100 ppm of NaCl, linear polarization resistance value increases from 1079199 Ohmcm2 to 2385141 Ohm cm2 ; corrosion current decreases from 4.036x10-8 to 0.1966 x 10 -8A/cm2 ; charge transfer resistance increases from 4291 Ohm cm2 to 48880 Ohm cm2 ; impedance value increases from 4.652 to 5.114; double layer capacitance decreases from 1.189 x10-9 to 1.0434 x10-10 F/cm2 , and phase angle increases from 61 to 88.","PeriodicalId":23842,"journal":{"name":"Zastita materijala","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87979312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of dilution and addition of soda water on the corrosion resistance of orthodontic wires immersed in artificial saliva in presence of Copper Barrel, a hard drink 苏打水的稀释和加入对人工唾液中含铜桶饮料正畸丝耐腐蚀性能的影响

Zastita materijala Pub Date : 2023-01-01 DOI: 10.5937/zasmat2302119a

Amala Suvakeen, K. Kavipriya, Senthil Vadivelan, Anu Ratthika, T. Vidhya, Sindhuja Jerleen, Nilavan Anitha, R. Srinivasan, S. Rajendran, T. Gowrani

{"title":"Influence of dilution and addition of soda water on the corrosion resistance of orthodontic wires immersed in artificial saliva in presence of Copper Barrel, a hard drink","authors":"Amala Suvakeen, K. Kavipriya, Senthil Vadivelan, Anu Ratthika, T. Vidhya, Sindhuja Jerleen, Nilavan Anitha, R. Srinivasan, S. Rajendran, T. Gowrani","doi":"10.5937/zasmat2302119a","DOIUrl":"https://doi.org/10.5937/zasmat2302119a","url":null,"abstract":"Copper barrel brandy can be taken orally with dilution of bisleri water or soda water and without dilution. People clipped with orthodontic wires may take copper barrel brandy orally, with dilution of without dilution. How far the orthodontic wires will be affected by these items? To find an answer the present research work is undertaken. Corrosion resistance of orthodontic wires made of Ni-Ti alloy and Ni-Cr alloy in artificial saliva in the absence and presence of copper barrel, water and soda water has been evaluated by AC impedance spectra. It is generally observed that Ni-Ti alloy is more corrosion resistant than Ni-Cr alloy in artificial saliva in the presence of copper barrel, water and soda water. When orthodontic wire made of Ni-Ti is immersed in artificial saliva, the charge transfer resistance (Rt) value is 31945Ohmcm2 . When it is immersed in copper barrel + artificial saliva (AS) system, Rtvalue increase to 80000Ohmcm2 . When it is immersed in soda water + artificial saliva (AS) system, Rtvalue increase to 76450Ohmcm2 . When it is immersed in water + artificial saliva (AS) system, Rtvalue increase to 82620Ohmcm2 . On the other hand, when orthodontic wire made of Ni-Cr is immersed in artificial saliva, the charge transfer resistance (Rt) value is 80930Ohmcm2 . When it is immersed in copper barrel + artificial saliva (AS) system, Rtvalue decrease to 11104Ohmcm2 . When it is immersed in soda water + artificial saliva (AS) system, Rtvalue decrease to 10437Ohmcm2 . It implies that the people who have been clipped with orthodontic wire made of Ni-Ti alloy can take copper barrel in any form, namely, with dilution or without dilution. The people who have been clipped with orthodontic wire made of Ni-Cr alloy should avoid taking copper barrel in any form, namely, with dilution or without dilution.","PeriodicalId":23842,"journal":{"name":"Zastita materijala","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79211144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A novel 2-D mathematical modeling to determine LHP to protect the industrial transient heat treatment quenched low carbon steels bar 建立了一种新的二维数学模型来确定保护工业瞬态热处理淬火低碳钢棒的LHP

Zastita materijala Pub Date : 2023-01-01 DOI: 10.5937/zasmat2303327e

A. Elmaryami, Amal Mohamed

引用次数: 0

Ion nitriding and surface alloying of H13A hard alloy cutting tools H13A硬质合金刀具的离子氮化及表面合金化

Zastita materijala Pub Date : 2023-01-01 DOI: 10.5937/zasmat2302161t

Toshbotirovich Doniyor

引用次数: 0