chemistry and materials research最新文献_第5页

USING OF LACCASE IN PAPERMAKING PROCESS FROM OLD CORRUGATED CONTAINER (OCC) PULP 漆酶在旧瓦楞纸浆造纸中的应用

chemistry and materials research Pub Date : 2021-11-01 DOI: 10.7176/cmr/13-3-04

N. Elyani

{"title":"USING OF LACCASE IN PAPERMAKING PROCESS FROM OLD CORRUGATED CONTAINER (OCC) PULP","authors":"N. Elyani","doi":"10.7176/cmr/13-3-04","DOIUrl":"https://doi.org/10.7176/cmr/13-3-04","url":null,"abstract":"Nina Elyani (Corresponding author), Sonny Kurnia Wirawan, Nena Andrina Restu Center for Pulp and Paper Jl. Raya Dayeuh Kolot 132 Bandung, West Java, Indonesia Tel: +62-22-5202980 E-mail: ninaelyani@yahoo.com, sonny-k@kemenperin.go.id Abstract Old Corrugated Container (OCC) is one of the most potential raw material for paper and paperboard manufacture but it has some disadvantage of a continued decrease in the quality of the fiber during the recycling process. It’s caused by decreasing of carboxyl groups when the fibers undergo drying, resulting in decreased ability for swelling, thereby reducing the ability of the bond between the fiber and the fiber strength. Modification of waste paper using laccase enzyme may increase the fiber content of the carboxyl group of waste paper, therefore will increase paper strength. Experiments carried out with the addition of laccase in various dosage paper stock originating from OCC by 5% pulp consistency. 80 g/m Laboratory sheets, was made from stock, then analyzed by tensile index, burst index, wet tensile index, the content of carboxyl groups and SEM analysis. The experimental results showed addition of 50 U/g laccase at OCC giving optimum value for physical properties.","PeriodicalId":9724,"journal":{"name":"chemistry and materials research","volume":"C-20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85067444","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

Maize Husk Ash as a Renewable Source for the Production of Value Added Silica Gel and Its Application 玉米壳灰作为可再生原料生产高附加值硅胶及其应用

chemistry and materials research Pub Date : 2021-10-01 DOI: 10.7176/cmr/13-3-01

A. Ananthi, D. Geetha, P. Ramesh

{"title":"Maize Husk Ash as a Renewable Source for the Production of Value Added Silica Gel and Its Application","authors":"A. Ananthi, D. Geetha, P. Ramesh","doi":"10.7176/cmr/13-3-01","DOIUrl":"https://doi.org/10.7176/cmr/13-3-01","url":null,"abstract":"Nowadays, silica gels have developed a lot of interest due to their extraordinary properties and their existing and potential applications in science and technology. Silica gel has a lot of applications such as a desiccant, as a preservation tool to control humidity, as an adsorbent, as a catalyst and as a catalyst support. Silica gel is a rigid three-dimensional network of colloidal silica, and is classified as: aquagel, xerogel and aero-gel. Extraction of amorphous silica from Maize Husk Ash (MHA) was carried out in this study. Silica xerogel was produced by dissolving MHA with alkali solution to form sodium silicate solution and lowering the pH to7 by adding hydrochloric acid to form silica aquagel followed by drying to form silica xerogel. The silica xerogel was characterized using SEM, XRD and FTIR techniques. Silica and mineral contents of MHA and xerogel were determined by EDS, X-ray diffraction patterns revealed amorphous nature of extracted silica. Fourier transform infrared (FTIR) data indicates the presence of siloxane and silanol groups. Silica yield from MHA was 56.32% while moisture content was 2.89% and also the SEM presented appropriated morphological characteristics of the best silica. MHA proved to be a potential low cost raw material for the production of silica gel.","PeriodicalId":9724,"journal":{"name":"chemistry and materials research","volume":"32 4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83960980","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

Study of the Level of Polycyclic Aromatc Hydrocarbons (PAHs) in Some Locally Smoked Fish Species 几种本地熏鱼中多环芳烃含量的研究

chemistry and materials research Pub Date : 2021-10-01 DOI: 10.7176/cmr/13-3-03

Á., Ogiedu

{"title":"Study of the Level of Polycyclic Aromatc Hydrocarbons (PAHs) in Some Locally Smoked Fish Species","authors":"Á., Ogiedu","doi":"10.7176/cmr/13-3-03","DOIUrl":"https://doi.org/10.7176/cmr/13-3-03","url":null,"abstract":"Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic pollutants which get into foods during processing. In spite of this, only a few studies have been carried out on Nigerian delicacies. This study was used to determine the level of PAHs in some smoked fish species namely: clarias gariepenus (catfish) , scomber scombrus (atlantic mackerel) and clupea harengus (herring fish). The fish species were smoked with a local open-fire fish smoking drum and PAHs were determined using the Gas Chromatography (GC) coupled with flame ionization detector (FID). The levels of PAHs were evaluated on the three species of fish. The total values of PAHs have shown that the smoked clarias gariepenus (catfish) , scomber scombrus (mackerel fish) and clupea harengus (herring fish) have 80.01µg/g, 69.94µg/g and 154.08µg/g respectively. Higher values were found in benzo(a)pyrene and lower values found in naphthalene. For benzo(a)pyrene, the values were 9.20µg/g, 2.90µg/g and 40.13 µg/g respectively. For naphthalene, the values were 1.13µg/g, 1.11µg/g and 1.72µg/g respectively. Benzo(a)pyrene, which is highly carcinogenic was found to have the highest concentration in clupea harengus (herring fish) of about 40.13µg/g which is above permissible level. As for the other PAHs, they were all detected in various quantities which resulted to the high level of the total PAHs in the samples. From the study, it was revealed that the open-fire fish smoking pose a health risk for human as it is being contaminated. It is therefore recommended that a low polycyclic aromatic hydrocarbons (PAHs) improved fish smoking kiln should be developed.","PeriodicalId":9724,"journal":{"name":"chemistry and materials research","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85556920","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

Synthesis and Characterization of Schiff Bases Derived from 1-Naphthylamine Hydrochloride, Syria: Homs 盐酸1-萘胺席夫碱的合成与表征，叙利亚:Homs

chemistry and materials research Pub Date : 2021-10-01 DOI: 10.7176/cmr/13-3-02

Rawand Alsabra

引用次数: 0

ANTI-CORROSION POTENTIALS OF FRESH EXTRACTS OF OLD PERSEA AMERICANA VAR. AMERICANA SEED IN 0.5 M H2SO4 ON MILD STEEL 美洲古树种子新鲜提取物在0.5 m h2so4中对低碳钢的防腐性能

chemistry and materials research Pub Date : 2021-06-01 DOI: 10.7176/cmr/13-2-03

引用次数: 0

Biosorptive Removal of Hexavalent Chromium by Rice Husk Ash and Silica from Aqueous Solution 稻壳灰和二氧化硅对六价铬的生物吸附去除研究

chemistry and materials research Pub Date : 2021-01-01 DOI: 10.7176/cmr/13-1-02

E. Aikhoje

{"title":"Biosorptive Removal of Hexavalent Chromium by Rice Husk Ash and Silica from Aqueous Solution","authors":"E. Aikhoje","doi":"10.7176/cmr/13-1-02","DOIUrl":"https://doi.org/10.7176/cmr/13-1-02","url":null,"abstract":"Hexavalent chromium ion removal by adsorption using rice husk ash and silica prepared from rice husks obtained locally from rice mill as biosorbents was evaluated as low cost wastewater treatment in this study. Batch equilibrium isotherm experiments were performed as well as effect of dosage and initial chromate solution pH to determine the potentials of the sorbent to remove hexavalent chromate ion from synthetic fed wastewater. Equilibrium isotherm experimental data isotherms were tested with isotherm models (Langmuir, Freundlich and Tempkin models), being best represented by the Langmuir model. Optimum conditions were: dosage = 0.5 g / 200 ml at room temperature and pH o > 6. The equilibrium between adsorbate in the solution and on the adsorbent surface was practically achieved in 2 h. The monolayer sorption capacity was 67.45 mg/g for rice husk silica and 55.98 mg/g for rice husk ash. Estimation of energy of the sorption process revealed chemisorption as the prevailing means of interaction between the adsorbents and adsorbates moieties. The abundance and affordable (cheap) cost of rice husks justifies its use as a precursor in the preparation of rice husk ash and silica as effective adsorbents for chromium removal from industrial effluents. Graphical Abstract:","PeriodicalId":9724,"journal":{"name":"chemistry and materials research","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83382189","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 Behavior of Variable Zone for Concave Arcs -Fin of Heat Sink with Multi Air Jet Impingement 多气流冲击下散热器凹弧翅变区特性研究

chemistry and materials research Pub Date : 2021-01-01 DOI: 10.7176/cmr/13-2-02

Dalmn Yaseen Taha

{"title":"The Behavior of Variable Zone for Concave Arcs -Fin of Heat Sink with Multi Air Jet Impingement","authors":"Dalmn Yaseen Taha","doi":"10.7176/cmr/13-2-02","DOIUrl":"https://doi.org/10.7176/cmr/13-2-02","url":null,"abstract":"Novel array arcs- fin heat sink 7×2 with 6×2 multi air jet impingement are presented in this paper by using numerical simulation. Temperature distribution of jets diameter of 5mm and arcs- fin heat sink with variety shapes at constant radius of 45mm are evaluated. Reynolds number ranges from 7000 – 11000. The study has been done at constant Z/d= 6 and constant heat flux =8333.33 W/m 2 . The best shapes of fins has an effective role in improving the rate of heat transfer .In this paper, the design concerned in arcs ships to construct fin geometry. Four concave arcs constricted the shape of fins heat sink for model A. This model has been changed to construct models (B-C-D-E) by reflect two concave arc from it to be convex arc. All five models at the same radius. The five configurations were comparative between each other and the best model comparative with flat plate heat sink. It is observed that model D of heat sink showed best temperature dissipation than the others. The results of this paper can help to select heat sink that meets a design's thermal, Power, packaging and cost requirements (specialized in arcs fins) with array of impingement jet, which is a popular used in cooling electronic devices.","PeriodicalId":9724,"journal":{"name":"chemistry and materials research","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83899509","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 Effect of Grain Refining of Primary Aluminum on the Fluidity of Al-Si Casting Alloys 原铝晶粒细化对Al-Si铸造合金流动性的影响

chemistry and materials research Pub Date : 2021-01-01 DOI: 10.7176/cmr/13-1-05

A. Olusegun

引用次数: 0

Stir Bar Sorption Extraction (SBSE) and Its Application for Analysis of Organic Compounds in Aqueous Samples: A Review 搅拌棒吸附萃取(SBSE)及其在水中有机物分析中的应用综述

chemistry and materials research Pub Date : 2021-01-01 DOI: 10.7176/cmr/13-1-01

Mesfin Medihin Ododo

{"title":"Stir Bar Sorption Extraction (SBSE) and Its Application for Analysis of Organic Compounds in Aqueous Samples: A Review","authors":"Mesfin Medihin Ododo","doi":"10.7176/cmr/13-1-01","DOIUrl":"https://doi.org/10.7176/cmr/13-1-01","url":null,"abstract":"Sample preparation is one of the crucial steps in any chemical analysis because most samples are not ready to introduce directly into analytical instruments. This step is very important to eliminate interferences, isolate and preconcentration of analytes of interest from the matrix and makes them more suitable for separation and detection. The extraction of analytes from aqueous matrices can be traditional and nontraditional techniques. Miniaturized techniques are simple, solventless or solvent-reduced techniques allowing the extraction and concentration in a single step on a micro scale approach. Stir Bar Sorptive Extraction (SBSE) is a relatively new solventless sample preparation method for the extraction and concentration of organic compounds from aqueous matrices of environmental, food and biological samples. In SBSE, a stir bar coated with Polydimethylsiloxane (PDMS) phase is added to a vial containing the sample. The sample is then stirred until analytes partition equilibrium time reached with sorbent. The extracts can be introduced quantitatively into the analytical system by thermal or liquid desorption. The efficiency of extraction of SBSE in terms of the amount extracted and the equilibrium is affected by extraction time, stirring speed, temperature of the sample, pH, salting and sample volume. The most important limitation of SBSE is the only commercial availability of PDMS coating material exists at present. Besides, due to the non-polar character of PDMS, SBSE technique is mainly applied to extract non-polar and weakly polar compounds but failed in extraction of strongly polar compounds.","PeriodicalId":9724,"journal":{"name":"chemistry and materials research","volume":"45 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85886671","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 Tracking Review on Non Arc Melting Processes for Improved Surface Properties in Metallic Materials 改善金属材料表面性能的非电弧熔炼工艺研究进展

chemistry and materials research Pub Date : 2021-01-01 DOI: 10.7176/cmr/13-2-01

O. W. Subair, M. Amuda, E. Akinlabi, G. Lawal

{"title":"A Tracking Review on Non Arc Melting Processes for Improved Surface Properties in Metallic Materials","authors":"O. W. Subair, M. Amuda, E. Akinlabi, G. Lawal","doi":"10.7176/cmr/13-2-01","DOIUrl":"https://doi.org/10.7176/cmr/13-2-01","url":null,"abstract":"Most metallic materials lack the adequate surface characteristics to satisfactorily perform intended service functions. In such instance, the surface properties are modified by altering the chemistry, structure and/topology of the top surface of the surface via modification techniques. There exists wide options of techniques for modifying the surface properties and these are well documented in the literature. However, these techniques have different scientific underpinnings controlling them such that it is difficult to use a single mechanism to characterize the techniques. Arising from this, it is imperative that a holistic understanding of the various processes is provided. Therefore, in this paper, research status on the wide range of non-melting technique for surface modification is presented. The presentation discusses the investigation conducted on the various non-surface melting techniques and provides a comparison across the techniques. Recent developments in these techniques are equally presented. Existing challenges and emerging trends in the field are also highlighted. . to chromium carbide was equally studied. The results indicated that suitable time for complete transformation of the most stable carbide phase Cr 3 C 2 was achieved by heating the chromium coated fiber for 6 h in vacuum at 900 °C. has been presented. The progression of surface modification from the basic thermochemical treatment through conversion coating to vapour deposition","PeriodicalId":9724,"journal":{"name":"chemistry and materials research","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80438977","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