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Phosphoric Acid Pretreatment and Saccharification of Paper Sludge as a Renewable Material for Cellulosic Fibers

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Journal of Renewable Materials 2024年第9期12卷 1573-1591页

作者： Samar El-Mekkawi Wafaa Abou-Elseoud Shaimaa Fadel Enas Hassan Mohammad Hassan Chemical Engineering and Pilot Plant Department National Research CentreDokkiGiza12622Egypt Cellulose and Paper Department National Research CentreDokkiGiza12622Egypt

Recycling of paper sludge waste is crucial for establishing a sustainable green *** waste contains valuable sugars that can be converted into important chemicals such as ethanol,poly hydroxybutyrate,and lactic ***,the main challenge in obtaining sugars in high yield from paper sludge is the high crystallinity of cellulose,which hinders *** address this,pretreatment using phosphoric acid was optimized using response surface methodology to facilitate cellulose hydrolysis with minimal energy and *** created prediction model using the response surface method considered factors such as acid concentration(ranging from 60%to 85%),consistency(ranging from 4%to 10%),temperature(ranging from 25℃to 80℃),and time(ranging from 0.5 to 4 h).The results revealed that the model’s significant factors affecting the yield were acid concentration,reaction time,temperature,and the product of acid concentration and temperature,while the model’s significant factors affecting the crystallinity were the consistency,the temperature,and their *** results showed that the optimum conditions for pretreatment were using an acid concentration of 64%,temperature of 25℃,consistency of 10%,and time of 30 *** hydrolysis of the conditionally pretreated paper sludge resulted in a weight loss of 42%,compared to only 18%weight loss in non-pretreated paper ***,the optimized conditions led to low levels of furfurals and acetic acid,which are undesirable by-products that can interfere with sugar *** total sugar obtained under the optimized conditions was 0.43 g glucose/g sample(10.46 g/L),while the contents of methyl furfural,furfural,and acetic acid were 21.65,235.7,and 4.57 mg/L,*** study demonstrates the potential of phosphoric acid for pretreatment and hydrolysis of paper sludge,enabling efficient saccharification and the production of sugars with minimal undesired by-products.

关键词： Waste valorization fermentable sugars response surface methodology acid hydrolysis cellulose crystallinity

Evaluating mechanism of banana pseudo-stem retting using seawater:A cost-effective surface pre-treatment approach

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Journal of Bioresources and Bioproducts 2024年第3期9卷 322-335页

作者： Prince Hotor Ahmed H.Hassanin Osbert Akatwijuka Mohamed A.H.Gepreel Mitsuo Yamamoto Yukie Saito Ahmed Abdel-Mawgood Egypt-Japan University of science and technology Biotechnology ProgramAlexandria GovernorateNew Borg Al Arab 21934Egypt Alexandria University Department of Textile EngineeringAlexandria GovernorateBab Sharqi 5424041Egypt Egypt-Japan University of science and technology Material Science and EngineeringAlexandria GovernorateNew Borg Al Arab 21934Egypt Graduate School of Agricultural and Life sciences The University of TokyoBunkyo-KuTokyo 113-8657Japan

Retting has been employed to extract natural fibers from agricultural wastes as a biological and cost-effective approach for *** its global abundance,banana pseudo-stem is a promising agro-waste for lignocellulosic fiber *** this study,fibers were extracted from the pseudo-stems after being pre-treated under four conditions using seawater at room temperature for up to 35 d Bacterial isolation from the fresh seawater sample and screening for ligninolytic ability were *** load as well as laccase and manganese peroxidase enzyme activity profile assay during the retting duration were *** transform infrared(FT-IR)and X-day diffraction(XRD)analyses were also examined for both pre-treated and untreated extracted *** results shows that six out of the eight bacterial isolates had the ability to degrade *** treatments(Raw stem+Raw seawater)and(Autoclaved stem+Raw seawater)recorded the highest viable bacterial load of 9.24×102 and 4.46×102 CFU,respectively,on the 14th day of the retting ***,the highest laccase and manganese peroxidase enzymes activity was recorded for(Raw stem+Raw seawater)and(Autoclaved stem+Raw seawater)treatments in the second to the third *** FT-IR spectra of the pre-treated fibers revealed relative reductions in peaks attributed to polysaccharides and other amorphous substances for all retting *** XRD diffractogram revealed that the crystallinity index(CI)of pre-treated fibers increased in all seawater retting treatment ***,the CI for fibers pre-treated under enzymatic conditions were enhanced even after five *** analysis for selected bacterial isolates showed homology to sequences of Bacillus velezensis,Shewanella sp.L8–5,and Citrobacter amalonaticus and Bacillus subtilis j8 *** these findings,it was suggested that physical,biological,and chemical actions were collectively involved in the seawater retting process of banana ps

关键词： Seawater retting Banana pseudo-stem Natural fiber Enzyme activity Colony forming unit

Ultrafast laser dynamics of metal organic frameworks/TiO_2 nano-arrays hybrid composites for energy conversion applications

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Journal of Energy Chemistry 2019年第2期28卷 88-94页

作者： Fatma M.Ismail Daniel O'Neil Tareq Youssef Souad A.Elfeky The National Institute of Laser Enhanced sciences Cairo University Zewail City of science and technology Georgia Institute of technology

Herein,we report the victorious synthesis of metal-organic frameworks(MOFs) on TiO_2 nanotubes(NTs)using a layer-by-layer(LbL) *** crystalline and homogenous thin films of MOFs were grown and characterized using XRD,SEM,FT-IR and UV/Vis ***,the utilization of the MOF films as sensitizers was probed in bespoke Graetzel type liquid junction solar *** constructed cell performance revealed an I_(sc) of 1.16 mA cm^(–2),Vocof 0.63 V,FF of 0.33,and E_(ff) of 0.42%.Further,pumpprobe transient laser spectroscopy was performed to investigate the energy and charge transfer dynamics of the MOFs/TiO_2 NTs *** results indicated 86% injection *** ultrafast pump-probe spectroscopy allows the investigation of this process and the differences between *** also showed that the relaxation of the MOF chromophores is in competition with electron injection in the Ti O2 *** this study provides a new insight into electron transfer from photoexcited metal-organic frameworks(MOFs) into titanium dioxide.

关键词： Ultrafast laser dynamics Metal-organic frameworks TiO2 nano-arrays Energy conversion Thin film

Electroconductive Composites Containing Nanocellulose,Nanopolypyrrole,and Silver Nanoparticles

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Journal of Renewable Materials 2019年第2期7卷 193-203页

作者： Samir Kamel Ahmed A.Haroun Amany M.EI-Nahrawy Mohamed A.Diab Cellulose and Paper Department National Research Centre33 El Bohouth st.Dokki GizaP.O.12622Egypt Industrial Research Division National Research Centre33 El Bohouth st.Dokki GizaP.O.12622Egypt Solid State physics Department Physics Research DivisionNational Research Centre33 El Bohouth st.Dokki GizaP.O.12622Egypt

In this work,conducting composites of nanocellulose(NC)/polypyrrole nanoparticles(NPPy)and silver nanoparticles(AgNPs),i.e.,NC/NPPyAg,were synthesized for the first time,to the best of our knowledge,via in situ emulsion polymerization of pyrrole in the presence of surfactant *** AgNPs acted as an oxidizing agent to simultaneously incorporate nanoparticles into the prepared *** structures and morphologies of the prepared composites were studied using Fourier transform infrared(FTIR)spectroscopy,X-ray diffraction(XRD),UV-Vis Spectra,thermogravimetric analysis(TGA),and scanning and transmission electron microscopy(SEM and TEM)***,the prepared composites were characterized by their conductivities,and the dielectric constants(e΄),dielectric losses(e˝),and AC conductivities were studied for the prepared composites with an increasing NPPy content as a function of the frequency.

关键词： Nanocellulose nanopolypyrrole emulsion polymerization silver nanoparticles conductive nanocomposites

Effect of Y^(3+), Gd^(3+) and La^(3+) dopant ions on structural, optical and electrical properties of o-mullite nanoparticles

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Journal of Rare Earths 2014年第1期32卷 37-42页

作者： M.M.S.Sanad M.M.Rashad E.A.Abdel-Aal M.F.El-Shahat K.Powers Central Metallurgical R & D Institute Particle Engineering Research Center University of Florida Faculty of science Ain Shams University

Dielectric ceramics of M（x）Al6（1-x）Si2O13 doped mullite were synthesized via co-precipitation technique. The X-ray diffrac-tion profiles revealed that these nanoparticles were crystallized well and the volume of mullite unit cell was increased as a function of the ionic radius of dopant ion. TEM images showed regular orthorhombic crystal morphology for the pure mullite sample. Meanwhile, the doped samples exhibited slightly distorted crystal morphology of larger particle sizes. DSC thermograms evinced that the exo-thermic peak temperature of mullite was shifted to the lower value with M3＋ion insertion. The photoluminescence spectra were stud-ied for mullite samples, and it was found that the intensity of the emission spectra was affected by the M3＋ion type. It was found that, Y3＋doped mullite achieved the minimum dielectric loss value of 0.01 in the radio wave frequency region （1 MHz）. Meanwhile, Gd3＋doped mullite achieved the minimum dielectric loss value of 0.09 in the microwave frequency region （1 GHz）.

关键词： rare earths doped mullite photoluminescence crystallization temperature dielectric ceramics

Controls on lode gold mineralization,Romite deposit,South Eastern Desert,Egypt

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Geoscience Frontiers 2012年第5期3卷 571-585页

作者： Basem A.Zoheir Department of Geology

Field and remote sensing studies reveal that Au-bearing quartz carbonate lodes in Romite deposit, in the extreme South Eastern Desert of Egypt, are controlled by NNE-striking shear zones that splay from the ca. 660--550 Ma Hamisana Zone. Quartz in releasing bends with sinistral shear geometry and abundant boudinaged quartz-carbonate lodes with serrate ribboned fabrics suggest vein formation throughout a transpressive wrench system. Ubiquitous hydrothermal quartz, carbonate, and subordinate chlorite and sericite within the shear zones and as slivers in veins, indicate that gold deposition and hydro- thermal alteration occurred under greenschist facies conditions. The AI （IV） in chlorite indicates a forma- tion temperature of - 300 ℃, comparable with temperatures estimated from arsenopyrite composition for grains intimately associated with gold in quartz veins. The new geological and geochemical data indicate that splays off the Hamisana Zone are potential gold exploration targets. Quartz veins along the high order （2nd or 3rd） structures of this crustal-scale shear zone are favorable targets. In the Romite deposit and in surrounding areas, a Au-As-Cu-Sb-Co-Zn geochemical signature characterizes mineralized zones, and particularly rock chips with 〉 1000 ppm As and high contents of Cu, Zn, and Co target the better mineralized areas. The carbonate δ13CpDB and δ18OsMow isotope signatures preclude an organic source of the ore fluid, but metamorphic and magmatic sources are still valid candidates. The intense deformation and lack of mag- matism in the deposit area argue for metamorphic dewatering of greenstone rocks as the most likely fluid source. The narrow ranges of δ13C （-4.6‰ to -3.1‰） and 6180 （11.9‰- 13.7‰） in carbonate minerals in lodes imply a corresponding uniformity to the ambient temperature and δ13CCO2 （δ13C∑C） of the ore *** calculated δ18OH2O values of 6‰-7.9‰for ore fluids, based on 6180 values of vein quartz further suggest a likely metamorphic o

关键词： Romite gold deposit Orogenic lodes Hamisana Zone Stable isotopes Egypt

Cost-effective integrated strategy for the fabrication of hard-magnet barium hexaferrite powders from low-grade barite ore

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International Journal of Minerals,Metallurgy and Materials 2016年第9期23卷 991-1000页

作者： M.M.S.Sanad M.M.Rashad Central Metallurgical R & D Institute

Ultrafine barium hexaferrite（BaFe12O19） powders were synthesized from the metallurgical extracts of low-grade Egyptian barite ore via a co-precipitation route. Hydrometallurgical treatment of barite ore was systematically studied to achieve the maximum dissolution efficiency of Fe（～99.7%） under the optimum conditions. The hexaferrite precursors were obtained by the co-precipitation of BaS produced by the reduction of barite ore with carbon at 1273 K and then dissolved in diluted HCl and FeCl3 solution at pH 10 using NaOH as a base; the product was then annealed at 1273 K in an open atmosphere. The effect of Fe^3＋/Ba^2＋ molar ratio and the addition of hydrogen peroxide（H2O2） on the phase structure, crystallite size, morphology, and magnetic properties were investigated by X-ray diffraction, scanning electron microscopy, and vibrating sample magnetometry. Single-phase BaFe（12）O（19） powder was obtained at an Fe^3＋/Ba^2＋ molar ratio of 8.00. The formed powders exhibited a hexagonal platelet-like structure. Good maximum magnetization（48.3 A×m^2×kg^–1） was achieved in the material prepared at an Fe^3＋/Ba^2＋ molar ratio of 8.0 in the presence of 5% H2O2 as an oxidizer and at 1273 K because of the formation of a uniform, hexagonal-shaped structure.

关键词： chemical process barite ore treatment characterization magnetic properties ferrites

Biological and molecular studies on specific immune cells treated with checkpoint inhibitors for the thera-personal approach of breast cancer patients(ex-vivo study)

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Oncology Research 2021年第5期29卷 319-330页

作者： MOTAWA E.EL-HOUSEINI MOSTAFA S.ARAFAT AHMED M.EL-HUSSEINY ISLAM M.KASEM MAHMOUD M.KAMEL AHMED H.EL-HABASHY MEDHAT M.KHAFAGY ENAS M.RADWAN MAHA H.HELAL MONA S.ABDELLATEIF Medical Biochemistry and Molecular Biology Cancer Biology DepartmentNational Cancer InstituteCairo UniversityCairo11976Egypt Biotechnology Department Faculty of ScienceCairo UniversityGiza12613Egypt Zoology department Faculty of ScienceCairo UniversityGiza12613Egypt Clinical Pathology Department National Cancer InstituteCairo UniversityCairo11976Egypt Department of Pathology National Cancer InstituteCairo UniversityCairo11976Egypt Surgical Oncology Department National Cancer InstituteCairo UniversityCairo11976Egypt Radio-Diagnosis Department National Cancer InstituteCairo UniversityCairo11976Egypt

Immunotherapy becomes a promising line of treatment for breast cancer(BC)however,its success rate is still ***:The study was designed to optimize the condition for producing an effective dendritic cell(DCs)based immunotherapy by using DCs and T lymphocytes together with tumor-inﬁltrating lymphocytes(TILs)and tumor-inﬁltrating DCs(TIDCs),treated with anti-PD1 and anti-CTLA4 monoclonal *** mixture of immune cells was co-cultured with autologous breast cancer cells(BCCs)isolated from 26 BC ***:There was a signiﬁcant upregulation of CD86 and CD83 on DCs(p=0.001 and 0.017,respectively),similarly upregulation of CD8,CD4 and CD103 on T cells(p=0.031,0.027,and 0.011,respectively).While there was a signiﬁcant downregulation of FOXP3 and combined ***8 expression on regulatory T cells(p=0.014 for both).Increased CD8/Foxp3 ratio(p<0.001)was also ***133,CD34 and CD44 were downregulated on BCCs(p=0.01,0.021,and 0.015,respectively).There was a signiﬁcant increase in interferon-γ(IFN-γ,p<0.001),lactate dehydrogenase(LDH,p=0.02),and a signiﬁcant decrease in vascular endothelial growth factor(VEGF,p<0.001)protein *** expression of FOXP3 and Programmed cell death ligand 1(PDL-1)were downregulated in BCCs(p<0.001,for both),similarly cytotoxic T lymphocyte antigen-4(CTLA4,p=0.02),Programmed cell death 1(PD-1,p<0.001)and FOXP3(p<0.001)were signiﬁcantly downregulated in T ***:Ex-vivo activation of immune cells(DCs,T cells,TIDCs,and TILs)with immune checkpoint inhibitors could produce a potent and effective BC ***,these data should be validated on an experimental animal model to be transferred to the clinical setting.

关键词： Immunotherapy breast cancer PD1 CTLA4 TIDCs TILs

Isolation and characterization of marine-derived actinomycetes with cytotoxic activity from the Red Sea coast

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Asian Pacific Journal of Tropical Biomedicine 2016年第8期6卷 651-657页

作者： Mohamed Saleh Abdelfattah Mohammed Ismail Youssef Elmallah Usama Wahid Hawas Lamia Taha Abou El-Kassema Mennat Allah Gamal Eid Marine Natural Products Research Unit Faculty of Science Helwan University Marine Chemistry Department Faculty of Marine Sciences King Abdulaziz University Pharmacognosy Department National Research Centre

Objective: To isolate and evaluate the cytotoxic activity of different actinomycetes species isolated from the Red Sea coast in Sharm el-Sheikh, ***: Forty actinomycetes strains were isolated from different sediments and seawater samples collected from the Red Sea coast in Egypt. Actinomycetes were recognized by morphological and microscopic examinations. Cell viability and cytotoxicity induced by the crude extracts on breast cancer cell lines MDA-MB-231 were assessed using methylene blue assay. The strains with promising cytotoxic activity were identified by sequencing and amplifying the 16 S r RNA genes. The antibacterial activities of the crude extracts were performed using Kirby–Bauer disc diffusion ***: The results indicated that five ethyl acetate extracts exhibited cytotoxicity towards breast cancer cell lines MDA-MB-231. The highest cytotoxic activity was found for the ethyl acetate extracts of EGY2 and EGY39. The isolate EGY3 was identified as a new Streptomyces species, while the actinomycete EGY22 was found to be a member of the genus Nocardiopsis sp. The crude extract of the isolate EGY8 showed slightly high antimicrobial activity against different test ***: The results of the present study reveal that marine sediments of the Red Sea are a potent source of novel species of actinomycetes. The isolates may be useful in discovery of novel bioactive compounds and an important step in the development of microbial natural product research.

关键词： Red Sea Breast cancer Actinomycetes 16S rRNA Cytotoxicity