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Abstract In preparing the second edition of ‘Tanning Chemistry. The Science of Leather.’, the literature was updated and the content was revised and reviewed. Here, the new findings are presented and discussed. Notable developments include the necessary rethinking of the mechanism of sulfide unhairing because of new understanding of the aqueous chemistry of sulfide species. Revision upwards of the value of the second pKa for sulfide species ionisation means that S2− cannot exist in an aqueous medium, so the unhairing species in hair burn reactions is HS−. Although the technology remains the same, this means the mechanisms of associated reactions such as immunisation must be revised. Rawstock preservation has benefitted from studies of the potential role of materials from plants which accumulate salt, but which also contribute terpene compounds. There is also further discussion on the continuing issue of chromium (VI) in the leather industry. The application to processing of new solvents, ionic liquids and deep eutectics, is the coming technology, which offers transforming options for new chemistries and products. Renewed interest in vegetable tanning and methods of wet white processing are current trends. Also, within the topic of reagent delivery is processing in a solid medium of plastic beads. Graphical abstract

1-(5-Bromobenzofuran-2-yl)ethan-1-one has been employed as substrate in a direct Mannich reaction with common secondary amines to generate several β-aminoketones hydrochlorides. Alkylation of S- and N-nucleophiles (4-chlorothiophenol, piperazine, sulfanilamide, 3,5-dimethylpyrazole) with the dimethylamine-containing β-aminoketone derived from the aforementioned substrate has also been investigated. Reaction of the same ketonic Mannich base with phenylhydrazine afforded the corresponding 1,3-disubstituted pyrazoline, whose UV-Vis absorption has been measured in dimethylsulfoxide, toluene and chloroform at room temperature to give similar spectra having a maximum at approximately 390 nm. The fluorescence spectrum of this pyrazoline in toluene is more intense and blue-shifted compared to its emission spectrum in dimethylsulfoxide.

The gas processing facilities are designed to significantly reduce the impurities such as water vapor, heavy hydrocarbon, carbon dioxide, carbonyl sulfide (COS), benzene-toluene-xylene (BTX), mercaptan e , and the sulfur compounds. A small amount of those compounds in natural gas is not preferable since they disturb the next processes. It was proposed to decrease natural gas's operating temperature to -20 ⁰F to remove the impurities from natural gas. The decrease of the natural gas's operating temperature has some consequences to the gas mixers such as hydrate formation at high pressure and low temperature, solidification of ethylene glycol (EG) solution, and the icing of the surface due to low temperature on the surface of chiller (three constraints). The Aspen Hysys 8.8 was used to obtain the suitable flowrate and concentration of the EG solution injected into the natural gas. Peng-Robinson's model was considered the most appropriate thermodynamic property model, and thus it has been applied for this research. The calculation results showed that the EG solution injection would reduce the hydrate formation due to water vapor absorption in the natural gas by EG. The EG solution's flowrate and concentration were varied from 20,000-2,000,000 lb/hr and 80-90 wt.%. When the separation was carried out at the operating temperature of -20 ⁰F, the EG solution's concentration fulfilling the requirement was of 80-84 wt.% with the flowrate of EG solution of 900,000 lb/hr and even more. This amount is not operable. More focused investigation was done for the variation of the operating temperature. Increasing operating temperature significantly reduced the flowrate of EG solution to about 200,000 lb/hr. An alternative process was proposed by focusing on two concentration cases of 80 and 85 % of weight at the low flow rate of EG solution, respectively. These simulations were intended to predict impurities' concentration in the effluent of Dew Point Control Unit (DPCU). The concentrations of BTX, heavy hydrocarbon, mercaptan e , and COS flowing out of DPCU were 428.1 ppm, 378.4 ppm, 104 ppm, and 13.3 ppm, respectively. The concentrations of BTX and heavy hydrocarbon are greater than the minimum standard required. It is needed to install an absorber to absorb BTX and heavy hydrocarbon. However, the absorber capacity will be much smaller than if the temperature of natural gas is not decreased and not injected by the EG solution . Keywords : DPCU gas treatment ; ethylene glycol solution; hydrate formation ; simulation A B S T R A K Unit pengolahan gas dirancang untuk mengurangi sebagian besar senyawa pengotor seperti uap air, hidrokarbon berat, karbon dioksida, karbonil sulfida (COS), benzena-toluena-xilena (BTX), merkaptan, dan senyawa sulfur lainnya. Keberadaan senyawa tersebut dalam gas alam berbahaya karena mengganggu proses selanjutnya walaupun dalam jumlah sedikit. Untuk membersihkan gas alam dari senyawa pengotor, maka suhu operasi gas diturunkan menjadi -20 °F. Penurunan suhu operasi gas dapat menyebabkan pembentukan hidrat pada tekanan tinggi dan suhu rendah, pembekuan larutan etilena glikol (EG), dan pembentukan lapisan es pada permukaan chiller . Aspen Hysys 8.8 digunakan untuk memperkirakan berapa kecepatan alir dan konsentrasi larutan EG yang diinjeksikan ke gas alam. Model Peng-Robinson adalah model termodinamika yang diterapkan untuk penelitian ini. Hasil simulasi menunjukkan bahwa injeksi larutan EG dapat mengurangi pembentukan hidrat karena larutan EG menyerap uap air dalam gas alam. Kecepatan alir dan konsentrasi larutan EG divariasikan dari 20.000-2.000.000 lb/jam dan 80-90 % (%b/b). Saat pemisahan dilakukan pada suhu operasi -20 °F, konsentrasi larutan EG yang memenuhi syarat adalah 80-84 % (%b/b) dengan kecepatan alir larutan EG 900.000 lb/jam atau lebih. Jumlah ini sangat banyak dan kurang layak untuk dioperasikan. Penelitian difokuskan pada variasi suhu operasi. Peningkatan suhu operasi diikuti dengan pengurangan kecepatan aliran larutan EG secara signifikan yaitu menjadi sekitar 200.000 lb/jam. Alternatif proses diusulkan dengan berfokus pada penggunaan kecepatan alir larutan EG yang rendah dengan konsentrasi larutan EG sebesar 80 dan 85 % (%b/b). Simulasi dapat memprediksi konsentrasi pengotor yang keluar dari Dew Point Control Unit (DPCU). Konsentrasi BTX, hidrokarbon berat, merkaptan, dan COS yang mengalir keluar dari DPCU berturut-turut adalah 428,1 ppm, 378,4 ppm, 104 ppm, dan 13,3 ppm. Konsentrasi BTX dan hidrokarbon berat tersebut lebih besar dari standar minimum yang disyaratkan. Oleh karena itu, diperlukan pemasangan absorber untuk menyerap BTX dan hidrokarbon berat. Namun, kapasitas absorber akan jauh lebih kecil apabila dibandingkan dengan kondisi tanpa menurunkan suhu dan menginjeksikan oleh larutan EG. Kata kunci: DPCU; larutan etilena glikol; pembentukan hidrat; simulasi

حضور شکستگی‌های طبیعی در مخازن شکاف‌دار نقش مهمی در تعیین وضعیت تنش که تحت تأثیر تنش‌های تکتونیکی و آشفتگی محلی قرار دارد، ایفا می‌کند. جهت شکستگی، پایداری چاه و ناهمسانگردی تراوایی از جمله موارد وابسته به تغییرات تنش محلی هستند. امروزه برای درک بهتر رفتار ژئومکانیکی مخازن، اکثر مدل‌سازی‌های رفتار مکانیکی و هیدرولیکی با تغییرات تنش کوپل می‌شوند. در این پژوهش به منظور بررسی ارتباط بین تراکم شکستگی (به‌عنوان یکی از خواص هندسی شبکه شکستگی) و نیز بارگذاری تنش تکتونیکی زاویه‌دار، با تغییرپذیری تنش و کرنش برشی، ابتدا با استفاده از رویکرد تصادفی، شبکه شکستگی مجزا (DFN) ایجاد گردید. سپس با در نظر گرفتن ماهیت تانسوری تنش، میدان تنش با استفاده از نرم‌افزار FLAC2D بر پایه روش تفاضل محدود، تعیین شد. در نهایت داده‌های تنش با استفاده از روابط ریاضی مبتنی بر تانسور، مورد تجزیه و تحلیل قرار گرفت. در ادامه تأثیر چهار پارامتر مقاومت کششی سنگ، چسبندگی سنگ، سفتی نرمال شکستگی و زاویه اتساع شکستگی بر پراکندگی تنش در بارگذاری تحت زوایای مختلف، مورد ارزیابی قرار گرفت. نتایج نشان داد که آشفتگی تنش و واریانس مؤثر که معرف پراکندگی توزیع تنش است، با تراکم شکستگی که به‌صورت تعداد شکستگی بر واحد سطح با استفاده از رویکرد نمونه‌برداری پنجره‌ایی تعریف می‌شود، رابطه مستقیم دارد. همچنین مشاهده شد که جهت بارگذاری در تغییرپذیری تنش کل تأثیرگذار بوده و واریانس مؤثر، در زاویه بارگذاری °50 دارای بیشترین و در °170 دارای کمترین مقدار است. در میان پارامترها، مشخص گردید که سفتی نرمال بیشترین تأثیر را در توزیع تنش داشته و تأثیر پارامترهای سنگ بسیار ناچیز است. به‌طور کل می‌توان گفت توزیع و پراکندگی تنش در یک شبکه شکستگی متراکم با سفتی نرمال GPa/m 500 و زاویه بارگذاری °50، دارای مقدار بیشینه است.

در این پژوهش به بررسی فرآیند هیدرودی‌اکسیژناسیون کاتالیزوری انیسول مشتق شده از لیگنین برروی کاتالیزور Pt/Al2O3 در دماهای K 673-573، فشار bar 14-8 و سرعت فضایی g anisole/g catalyst˟h20-3 در راکتور لوله‌ای با بستر ثابت در حضور گاز هیدروژن به‌عنوان یکی از واکنش‌دهنده‌ها پرداخته شده است. واکنش‌های اصلی در فرآیند تبدیل کاتالیستی انیسول، شامل هیدروژن کافت، هیدرودی اکسیژناسیون، هیدروژن زدایی و ترانس آلکیلاسیون می‌باشد. در این فرآیند، ابتدا طی واکنش هیدروژن کافت، انیسول به فنول تبدیل می‌شود. سپس، مشتقات فنولی شامل 2- متیل فنول، 2,4- دی متیل فنول، 6،5،3،2- تترا متیل فنول طی فرآیندهای ترانس آلکیلاسیون و آلکیلاسیون تولید می‌شوند. بنزن نیز طی واکنش هیدرودی اکسیژناسیون تولید می‌شود. هم‌چنین، هگزا متیل بنزن به روش‌های آلکیلاسیون و هیدرودی اکسیژناسیون تشکیل می‌شود. شبکه واکنش و ثوابت سینتیکی واکنش‌ها براساس نتایج گزینش‌پذیری محصولات و میزان تبدیل انیسول، تعیین گردید. با توجه به نتایج به‌دست آمده از شبکه واکنش، فنول، 2- متیل فنول و بنزن محصولات اولیه فرآیند هیدودی اکسیژناسیون هستند. هم‌چنین براساس محاسبه‌های سینتیکی، تولید بنزن از سینتیک مرتبه اول پیروی نمی‌کند و تولید محصولات فنول، 2,4, 6-تری متیل فنول 2, 6 -دی متیل فنول، 2- متیل فنول، هگزا متیل بنزن و 6،5،3،2- تترا متیل فنول از سینتیک مرتبه اول پیروی کرده و انرژی فعا‌ل‌سازی برای تشکیل این محصولات به‌ترتیب kJ/mol 3/25، kJ/mol 2/40 ، kJ/mol 4/43، kJ/mol4/55، kJ/mol 1/70 و kJ/mol6/93 می‌باشد.

Upper gastrointestinal (GI) carcinomas are characterized as one of the deadliest cancer types with the highest recurrence rates. Their treatment is challenging due to late diagnosis, early metastasis formation, resistance to systemic therapy and complicated surgeries performed in poorly accessible locations. Current cancer medication face deficiencies such as high toxicity and systemic side-effects due to the non-specific distribution of the drug agent. Nanomedicine has the potential to offer sophisticated therapeutic possibilities through adjusted delivery systems. This review aims to provide an overview of novel approaches and perspectives on nanoparticle (NP) drug delivery systems for gastrointestinal carcinomas. Present regimen for the treatment of upper GI carcinomas are described prior to detailing various NP drug delivery formulations and their current and potential role in GI cancer theranostics with a specific emphasis on targeted nanodelivery systems. To date, only a handful of NP systems have met the standard of care requirements for GI carcinoma patients. However, an increasing number of studies provide evidence supporting NP-based diagnostic and therapeutic tools. Future development and strategic use of NP-based drug formulations will be a hallmark in the treatment of various cancers. This article seeks to highlight the exciting potential of novel NPs for targeted cancer therapy in GI carcinomas and thus provide motivation for further research in this field.

Lithium–oxygen batteries have attracted research attention due to their low cost and high theoretical capacity. Developing inexpensive and highly efficient cathode materials without using noble metal-based catalysts is highly desirable for practical applications in lithium–oxygen batteries. Herein, a heterostructure of NiFe and NiCx inside of N-doped carbon (NiCx-NiFe-NC) derived from bimetallic Prussian blue supported on biochar was developed as a novel self-standing cathode for lithium–oxygen batteries. The specific discharge capacity of the best sample was 27.14 mAh·cm−2 at a stable discharge voltage of 2.75 V. The hybridization between the d-orbital of Ni and s and p-orbitals of carbon in NiCx, formed at 900 °C, enhanced the electrocatalytic performance due to the synergistic effect between these components. The structure of NiCx-NiFe-NC efficiently improved the electron and ion transfer between the cathode and the electrolyte during the electrochemical processes, resulting in superior electrocatalytic properties in lithium–oxygen batteries. This study indicates that nickel carbide supported on N-doped carbon is a promising cathode material for lithium–oxygen batteries.

A triple-shape memory effect represents that polymers can memorize two temporary shapes and show a subsequent recovery from the second temporary shape to the first temporary shape and further to the permanent shape with heating, which provides more design freedom for the applications of shape-memory polymers. In this work, we investigate the shapememory performance of three polymers produced by a commercial 3D printer. Two polymers with a pure component exhibit distinct glass transition regions spanning 30°C for each material. The copolymer has a broader glass transition region from –4 to 59 °C. The dual-shape memory tests show that the deformation temperature has a limited influence on the two pure polymers, while a clear temperature memory effect can be observed in the copolymer. For the copolymer, the recovery region has only a small overlap when deformed at 60 and 20 °C, which allows programming two temporary shapes at these two temperatures. Both uniaxial tension tests and three-dimensional demonstration show that the copolymer exhibits a good triple-shape memory effect.

تشکیل رسوبات معدنی در چاه‌های تولیدی و تزریقی در صنعت نفت از جمله مشکلاتی است که اگر کنترل و پیشگیری نشود مشکلات بسیاری را به همراه خواهد داشت، به‌طوری‌که برای برطرف سازی و حذف آنها نیاز به صرف هزینه‌های زیاد اقتصادی برای تعمییر و تکمیل، عملیات اسیدکاری و انگیزش چاه و انواع بازدارنده‌ها می‌باشد. هدف از این پژوهش در ابتدا مدل‌سازی پروفایل‌های فشار و دما به همراه سایر خواص سیال تولیدی مخزن مانند چگالی، ویسکوزیته و دیگر پارامترهای تأثیرگذار به صورت درجا در چاه به کمک روش بگز و بریل و همچنین، مارچینگ الگوریتم می‌باشد به‌طوری‌که بتوان بدون استفاده از ابزار فیزیکی و درون چاهی خاص بدون صرف هزینه‌های زیاد اقتصادی در نقاط مختلف چاه در هر زمانی از فرآیند تولید از تشکیل رسوبات معدنی در هر نقطه از درون چاه آگاه شد. پس از تخمین شرایط ترمودینامیکی و فیزیکی سیال درون چاه، به بررسی وضعیت فیزیکی-شیمیایی سیال تولیدی در حالت‌های اشباع، فوق اشباع و زیر اشباع برای تشکیل رسوبات معدنی مسئله ساز با استفاده از محاسبه تغییرات غلظت و شاخص اشباع به کمک روش اودو و تامسون پرداخته و در نهایت با استفاده از مدل‌های ریاضی پتانسیل رسوب گذاری، نقاط (اعماق) بحرانی و مستعد برای رسوب‌گذاری را بررسی و ثبت کرد. هر چند ممکن است رسوبی که باعث توقف تولید چاه شود در محیط متخلخل باشد، اما این بررسی تنها درون چاه و در رشته تولیدی و لوله مغزی انجام شده است. نتایج حاصل از مدل‌سازی بر روی یکی از چاه‌های نفتی تحت نظر شرکت ملی مناطق نفت خیز جنوب به‌عنوان مطالعه موردی نشان داد که با افزایش عمق از سطح، شاخص رسوب‌گذاری برای رسوبات کلسیم سولفات نیمه آب دار(همی‌هیدارت) و استرانسیم سولفات در طول چاه تقریباً در تمام عمق‌ها منفی است و در نتیجه می‌توان گفت که احتمال تشکیل این رسوبات در اعماق مختلف این چاه وجود ندارد. همچنین برای رسوب کلسیم سولفات آب‌دار( ژیپس) تقریباً همین شرایط برقرار است. همچنین در نزدیکی سطح زمین شاخص اشباع این رسوب مثبت و کمی بزرگتر از صفر می باشد که نشان دهنده‌ی احتمال تشکیل رسوب ژیپس در این محدوده‌ی عمقی است. در نهایت، شاخص رسوب-گذاری برای رسوبات کلسیم سولفات بدون آب (انیدریت)، باریم سولفات و کلسیم کربنات (کلیست) همواره مثبت بوده که نشان دهنده‌ی وجود احتمال تشکیل این رسوبات در چاه می باشد.

تعیین نوع تخلخل، ریز رخساره‌ها و گونه‌های سنگی ابزارهای مهمی در شناخت توزیع ویژگی‌های مخزنی محسوب می‌شوند. هدف اصلی این مطالعه، بررسی این پارامترها در مخزن بنگستان میدان نفتی گچساران واقع در در ناحیه فرو افتادگی دزفول، جنوب‌غرب ایران، است. با استفاده از 200 مقطع نازک، انواع تخلخل و میکروفاسیس‌ها در سه چاه مخزن بنگستان، مورد بررسی قرار گرفت و بر این اساس، 4 میکروفاسیس تعیین گردید. در بررسی کیفیت مخزنی و به منظور شناسایی واحدهای مخزنی و غیرمخزنی، از روش تعیین واحدهای جریانی هیدرولیکی استفاده شد. تعیین واحدهای جریانی بر مبنای روش نمودار اصلاح شده چینه‌ای لورنز و نشانگر منطقه جریانی انجام شد. براساس نمودار لورنز، حداقل تعداد 4 واحد جریانی به‌دست آمد. توسط روش نشانگر منطقه جریانی 4 واحد جریانی و در نهایت، 4 گونه‏ سنگی مجزا (DRT) حاصل شد که هر یک از این واحدها، خصوصیات پتروفیزیکی مربوط به خود را دارا هستند. از DRT1 به‌سمت DRT4، خصوصیات مخزنی رو به بهبود هستند و بر میزان تراوایی افزوده می‏شود.

The curing kinetics of thermoset-thermoplastic compounds based on diglycidyl ether of bisphenol A (DGEBA), methyl tetrahydrophthalic anhydride (MTHPA) as the hardener, 2,4,6-tris(dimethylaminomethyl)phenol (DEH 35) as a catalyzer, and poly(lactic acid) (PLA) as workable (i.e., with repairable bonds) phase was investigated using Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). Hydrogen bonding between PLA carbonyl and epoxy hydroxyl and oxirane groups is the main influent interaction taking place, which acts as changing providers (i.e. hydrogen bonded groups able to move) of curing rate and degree of curing as evaluated from the vibration bands and exothermal released heat. With increasing PLA content, the real crosslink density decreases as also the curing rate is delayed. Partially miscibility between epoxy and PLA is proposed, whereas after reaching epoxy’s solubility limit PLA precipitates, hence the microstructure is suggested to be composed by the epoxy network, interacted Epoxy/PLA and precipitated PLA. Reported data offer reliable tools to reach the aimed degree of crosslinking, controlling of epoxy microstructure overcoming the brittle fracture providing a wider window of processing and applications.

This study is aimed at evaluating the impact of N- and S- bonding modes of thiocyanate substituent on catecholase activity as its presence in the coordination sphere of the metal complex can either reduce catecholase activity or otherwise. 4-Methyl-2-((piperidin-1- yl)methyl) phenol - the Mannich base and its synthesized metal complexes were characterized by various spectroscopic techniques including NMR, IR, and UV-Vis spectroscopy. Turnover rates obtained from the Cu(II) and Fe(III) complexes ranged between 6.02 - 22.72 h-1 with the thiocyanate mode in the Fe(III) complex leading to increased catecholase activity.

Lutein is a challenging compound to incorporate into food, as it is poorly soluble and unstable in aqueous solutions. In this study, the aim was to prepare stable encapsulates of lutein and lutein esters using feasible and straightforward techniques. Fine suspensions based on polyoxyethylene sorbitan monooleate and medium-chain triglyceride oil micelle-like units with 3.45% lutein esters or 1.9% lutein equivalents provided high encapsulation efficiencies of 79% and 83%, respectively. Lutein encapsulated in fine suspensions showed superior stability, as 86% was retained within the formulation over 250 days at 25 °C in the dark. Under the same storage conditions, only 38% of lutein remained in corresponding formulations. Higher encapsulation efficiencies were achieved with lecithin emulsions, at up to 99.3% for formulations with lutein, and up to 91.4% with lutein esters. In lecithin emulsions that were stored for 250 days, 17% and 80% of lutein and lutein esters, respectively, were retained within the formulations.

Glass is a familiar material that requires abundant mineral sources, with devastating consequences for the environment. Rice husk ash (RHA) presents a very high silica content (&gt, 95%) and it can be a very promising alternative source for silica in silica-based glass. However, impurities like manganese and iron, which depend on the rice harvest, might limit RHA use, particularly in the production of optical transparent glasses. In this work, we discussed how Mn and Fe can affect the coloring of the produced glass, and how the effect of these impurities can be removed. First, the RHA was treated with acid solutions, leading to the production of a soda-lime glass with similar transparency to commercial glass (&gt, 70%). Secondly, another simpler approach was studied: a small amount of antimony oxide was added in the composition of the glass, obtaining a transparent glass (&gt, 80%, same thickness) with RHA.

The experimental results regarding optical absorption and steady-state photoconductivity of amorphous single-layer structures (Al–As0.40S0.30Se0.30–Al, Al–Ge0.09As0.09Se0.82–Al, and Al–Ge0.30As0.04S0.66–Al) and of an amorphous heterostructure (Al–As0.40S0.30Se0.30/Ge0.09As0.09Se0.82/Ge0.30As0.04S0.66–Al) at different values of the voltage, with positive or negative polarity, applied to the illuminated top Al electrode are presented and discussed. The complex structure of the photocurrent spectra is attributed to the different values of the optical bandgap of the involved amorphous layers (Eg ≈ 2.0 eV for As0.40S0.30Se0.30 and Ge0.09As0.09Se0.82 and Eg ≈ 3.0 eV for Ge0.30As0.04S0.66). The obtained experimental results are discussed taking into account the light absorption depending on the nature and the thickness of each amorphous layer, on the wavelength, and on contact phenomena at the interfaces between different layers and between the amorphous layers and the metal electrodes with different work functions.

While the application of focused ion beam (FIB) techniques has become a well-established technique in research and development for patterning and prototyping on the nanometer scale, there is still a large underused potential with respect to the usage of ion species other than gallium. Light ions in the range of m = 1–28 u (hydrogen to silicon) are of increasing interest due to the available high beam resolution in the nanometer range and their special chemical and physical behavior in the substrate. In this work, helium and neon ion beams from a helium ion microscope are compared with ion beams such as lithium, beryllium, boron, and silicon, obtained from a mass-separated FIB using a liquid metal alloy ion source (LMAIS) with respect to the imaging and milling resolution, as well as the current stability. Simulations were carried out to investigate whether the experimentally smallest ion-milled trenches are limited by the size of the collision cascade. While He+ offers, experimentally and in simulations, the smallest minimum trench width, light ion species such as Li+ or Be+ from a LMAIS offer higher milling rates and ion currents while outperforming the milling resolution of Ne+ from a gas field ion source. The comparison allows one to select the best possible ion species for the specific demands in terms of resolution, beam current, and volume to be drilled.

Gene therapy has been explored as a future alternative for treating heart disease. Among several gene delivery systems aimed at penetrating specific target cells, we focused on safe and non-viral gene delivery materials with a high transfection efficiency. Although various techniques have been developed, the mechanisms underlying the cellular uptake of gene delivery materials have not yet been sufficiently studied in cardiomyocytes. The aim of this study was to determine how hydroxyapatite (HAp) nanoparticles contribute to the delivery of plasmid DNA (pDNA) into cardiomyocytes. We fabricated HAp nanoparticles using the water-in-oil (W/O) emulsion method and used these nanoparticles as the delivery vector for transfecting cardiomyocyte-derived HL-1 cells. HAp exhibited particles on the nanoscale and with a low cytotoxicity in HL-1 cells. The transfection assay performed with several endocytosis inhibitors suggested that the HAp/pDNA complexes were internalized by HL-1 cells through macropinocytosis. Furthermore, this HL-1 cell uptake was generated in response to HAp stimulation. Thus, HAp is a positive regulator of macropinocytosis in HL-1 cells and a good system for gene delivery in cardiomyocytes.

The goal of this work was to prepare a honeycomb-like pattern (HCP) structure by a combination of acetate cellulose and poly-L-lactic as biocompatible and biodegradable polymers used in tissue engineering. The formation was obtained by a fast and cheap solution-immersion phase separation method based on the presence of nonsolvent, which induces phase separation in normal air without surfactants and supports the formation of the honeycomb structure. As a substrate, we used plasma modified fluorinated polymer, which can significantly improve the possibility of successful preparation HCP formation and control pore size and dimension of the prepared porous layer. Honeycomb-like pattern structure from composite acetate cellulose-PLLA on the surface of plasma-treated perfluorinated polymer FEP was prepared with a simple technique. Plasma modification changed the surface chemistry, wettability and thus allowed the creation of HCP microporous structure on the perfluorinated substrate. The regularity, surface morphology, and wettability of HCP film can be effectively controlled by changing of plasma activation.

The tracking of body motion, such as bending or twisting, plays an important role in modern sign language translation. Here, a subtle flexible self-powered piezoelectric sensor (PES) made of graphene (GR)-doped polyvinylidene fluoride (PVDF) nanofibers is reported. The PES exhibits a high sensitivity to pressing and bending, and there is a stable correlation between bending angle and piezoelectric voltage. The sensitivity can be adjusted by changing the doping concentration of GR. Also, when the PES contacts a source of heat, a pyroelectric signal can be acquired. The positive correlation between temperature and signal can be used to avoid burns. The integrated sensing system based on multiple PESs can accurately recognize the action of each finger in real time, which can be effectively applied in sign language translation. PES-based motion-tracking applications have been effectively used, especially in human–computer interaction, such as gesture control, rehabilitation training, and auxiliary communication.

Thermoelectric generators made by large arrays of nanowires perpendicular to a silicon substrate, that is, so-called silicon nanowire forests are fabricated on large areas by an inexpensive metal-assisted etching technique. After fabrication, a thermal diffusion process is used for doping the nanowire forest with phosphorous. A suitable experimental technique has been developed for the measurement of the Seebeck coefficient under static conditions, and results are reported for different doping parameters. These results are in good agreement with numerical simulations of the doping process applied to silicon nanowires. These devices, based on doped nanowire forests, offer a possible route for the exploitation of the high power factor of silicon, which, combined with the very low thermal conductivity of nanostructures, will yield a high efficiency of the conversion of thermal to electrical energy.

Abstract The production of leather from animal skins and hides through tanning processes began in the pre-historic ages. Despite the origination of new leather making techniques such as chrome tanning which is being employed extensively today, the traditional method of leather production primarily through vegetable tanning is still being practised mostly in artisanal tanneries in developing nations including Ghana. Artisanal leather making, thus, contributes beneficially to rural livelihood. Nevertheless, the growth of this sector has been stifled by the lack of innovative technologies to enhance productivity. This challenge could be partly linked to the knowledge gap on the scientific principles governing artisanal leather production processes. This study, therefore, elaborates on various process steps and materials employed in traditional leather making in Ghana and the scientific principles underlying each of the processes. It also makes a comparison between traditional and modern leather manufacturing processes and identifies knowledge and technological gaps which would inspire in-depth scientific research into artisanal leather making. Graphical abstract

Contact-resonance AFM (CR-AFM) has been used in recent years for the measurement of mechanical properties of rather stiff materials, such as ceramics or metals, but also of some polymers. Compared with other techniques providing information on the mechanical properties of a sample, notably force–distance curves, CR-AFM has a much shorter acquisition time. This compensates in part the incomplete theoretical understanding of the underlying physical phenomena and of factors influencing the measurements. A commonly used method to analyze CR data requires the determination of the relative position of the tip, the calculation of the normalized contact stiffness, and the use of a calibration sample for the calculation of the elastic modulus of the sample. In the present paper, we propose an alternative procedure, based on approximations of the equations describing the system, which allows one to determine the elastic modulus of the sample as a parameter of the fit of the CR frequency as a function of the load. After showing that CR modes including scanning under continuous contact wear and damage the sample and/or alter the surface roughness, the results of point CR measurements on bulk and thin films are presented. Though Young’s moduli of bulk polystyrene and poly(methyl methacrylate) could be determined through the presented analysis, it is concluded that CR measurements are not appropriate for polymer samples. Major drawbacks are the bad resolution for moduli lower than ca. 10 GPa and the lack of a comprehensive physical model accounting for many factors affecting the dynamic response of a cantilever in contact with a sample.

Single-walled carbon nanotubes (SWCNTs) have attracted great interest regarding drug-delivery applications. However, their application has been limited by some inherent disadvantages. In this study, raw SWCNTs were purified with different oxidizing acids, and the resulting shortened CNTs were conjugated with poly(ethylene glycol) (PEG) and polyethylenimine (PEI). The different nanocarriers, that is, CNTs-COOH (CNTs), CNTs-PEG and CNTs-PEG-PEI, were systematically characterized and evaluated in terms of drug loading, in vitro release, cytotoxicity towards MCF-7 cells and cellular uptake. The results showed that all CNT carriers had a high drug loading capacity. In comparison with CNTs-COOH and CNTs-PEG, CNTs-PEG-PEI showed a more rapid drug release under acidic conditions and a higher antitumor activity. Furthermore, fluorescence detection and flow cytometry (FCM) analysis results indicated that the internalization into cells of CNTs-PEG-PEI was significantly enhanced, thus inducing tumor cell death through apoptosis more efficiently. The above series of benefits of CNTs-PEG-PEI may be attributed to their good dispersibility and comparably higher affinity to tumor cells due to the difunctionalization. In summary, the PEG- and PEI-conjugated CNTs may be used as novel nanocarriers and the findings will contribute to the rational design of multifunctional delivery vehicles for anticancer drugs.

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior INCT – Instituto nacional de ciência e tecnologia (Antigo Instituto do Milênio) Folds naturally appear on nanometrically thin materials, also called “2D materials”, after exfoliation, eventually creating folded edges across the resulting flakes. We investigate the adhesion and flexural properties of single-layered and multilayered 2D materials upon folding in the present work. This is accomplished by measuring and modeling mechanical properties of folded edges, which allows for the experimental determination of the bending stiffness (κ) of multilayered 2D materials as a function of the number of layers (n). In the case of talc, we obtain κ ∝ n3 for n ≥ 5, indicating no interlayer sliding upon folding, at least in this thickness range. In contrast, tip-enhanced Raman spectroscopy measurements on edges in folded graphene flakes, 14 layers thick, show no significant strain. This indicates that layers in graphene flakes, up to 5 nm thick, can still slip to relieve stress, showing the richness of the effect in 2D systems. The obtained interlayer adhesion energy for graphene (0.25 N/m) and talc (0.62 N/m) is in good agreement with recent experimental results and theoretical predictions. The obtained value for the adhesion energy of graphene on a silicon substrate is also in agreement with previous results.

Yttria stabilized zirconia (Y-TZP) is frequently used in dental and engineering applications due to its high strength and fracture resistance. In this study, 2Y-TZP samples were manufactured from commercially available powder produced by detonation synthesis. Tests of the mechanical properties exhibited an unusual combination of both very high strength and toughness. The materials show a very weak correlation between toughness and grain size. The transformability, measurable by XRD, cannot explain the high toughness. Fractographic analysis revealed a broad transformation affected zone with secondary cracks and shear bands on the tensile side of bending bars which can be made responsible for the high toughness and non-linear stress&ndash, strain curves.

0000-0003-3892-2775 0000-0001-5225-748X 0000-0002-2576-3085 WOS:000572422900005 Amphiphilic block copolymers are known to self-assemble into various morphologies, including ellipsoids, tubular structures, toroids, vesicles, micellar structures. In this paper, we discuss the synthesis of copolymeric nanostructures (CNs) using poly(2-ethyl-2-oxazoline)-block-poly(epsilon-caprolactone) (PEtOx-b-PCL) amphiphilic block copolymers. Our data indicate that - varying the molecular weight and the number of repeating units dictate the nature of morphology. That is, the formation of self-assembled morphologies from ellipsoid to rod-like architectures are observed in aqueous solution, depending on the mass ratio of the hydrophilic block (f(PEtOx)). To best of our knowledge, this is the first report on the morphological transitions of PEtOx-b-PCL amphiphilic block copolymer-based CNs with different f(PEtOx)) values in the literature. Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [213M725] The authors would like to thank the Scientific and Technological Research Council of Turkey (TUBITAK) for financial supports with grant number of 213M725.

The present work proposed a simple approach for producing a fibrous flexible resistive-type pressure sensor from wool. By dip-coating polyurethane (PU) and silver nanowires (AgNWs) onto wool yarn, the latter was turned into a coaxial cable-like structure with the electrically conductive AgNWs/PU composite sheath for the sensing functionality and the wool core for providing a pliable substrate of the sensor. Afterward, the overlapping region of two strands of orthogonally stacked conductive composite yarns was employed to act as the pressure sensor. The experimental results indicated that conductivity and durability of the conductive yarn and sensitivity of the pressure sensor are closely correlated and can be effectively tuned through changing the amounts of PU and AgNWs. The surface fine structure of the composite yarns is a key factor determining responsive behavior. As a result of optimization, the pressure sensor has acquired high sensitivity and longterm working stability. Moreover, the homemade PU imparted the sensor with sunlight triggered self-healability of microcracks. It is anticipated that the pressure sensor possesses promising application potential in a variety of areas, including wearable electronics and e-textiles.

The atomic arrangement of the Si(110)-(16×2) reconstruction was directly observed using noncontact atomic force microscopy (NC-AFM) at 78 K. The pentagonal structure, which is the most important building block of the reconstruction, was concluded to consist of five atoms, while only four or five spots (depending on tip bias) have been reported with scanning tunneling microscopy (STM). Single atoms were determined to exist near step edges between upper and lower terraces, which have not been reported using STM. These findings are key evidence for establishing an atomic model of the Si(110)-(16×2) reconstruction, which indeed has a complex structure.

In this work, a new type of self-powered, high-performance ultra-thin p-Si/n-ZnO nanowire (NW) flexible photodetector (PD) and its application as full-spectrum optical sensor and pyroelectric nanogenerator (PENG) are demonstrated. The working mechanism of PDs for PENGs is carefully investigated and systematically analyzed. The self-powered PDs exhibit high responsivity (1200 mA/W), high detectivity (1013 Jones) and fast response (τr = 18 μs, τf = 25 μs) under UV illumination. High and stable short-circuit output currents at each wavelength from ultraviolet (UV) to near-infrared (NIR) demonstrates that the device can realize full-spectrum optical communication. An experiment in which the PENG powers other devices is designed to further demonstrate the proposed working mechanism. This work provides an effective approach to realize self-powered, high-performance PDs for full-spectrum communication. Also, the fabrication of the PENG utilizing a simple and low-cost method shows its potential applications in self-powered flexible electronic devices.

We report the synthesis of α-Ag2S nanoparticles (NPs) by one-step laser ablation of a silver target in aqueous solution of thiourea (Tu, CH4N2S) mixed with cationic cetyltrimethylammonium bromide (CTAB) as surfactant. The effect of the CTAB surfactant on the structural, morphological, optical, and elemental composition of Ag2S NPs was evaluated using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and UV–vis spectroscopy. The optical absorption decreased and the optical energy gap of α-Ag2S increased from 1.5 to 2 eV after the CTAB surfactant was added to the Tu solution. XRD studies revealed that the synthesized Ag2S NPs were polycrystalline with a monoclinic structure and that crystallinity of the nanoparticles was improved after adding CTAB. Raman studies revealed the presence of peaks related to Ag–S bonds (Ag modes) and the longitudinal optical phonon 2LO mode. Scanning electron microscopy investigations confirmed the production of monodisperse Ag2S NPs when using the CTAB surfactant. The optoelectronic properties of α-Ag2S/p-Si photodetector, such as current–voltage characteristics and responsivity in the dark and under illumination, were also improved after using the CTAB surfactant. The responsivity of the photodetector increases from 0.64 to 1.85 A/W at 510 nm after adding CTAB. The energy band diagram of the α-Ag2S/p-Si photodetector under illumination was constructed. The fabricated photodetectors exhibited reasonable stability after three weeks of storage under ambient conditions with a responsivity of 70% of the initial value.

Methyl parathion (MP) is one of the most neurotoxic pesticides. An inexpensive and reliable one-step degradation method of MP was achieved through an aqueous suspension of copper(I) oxide nanoparticles (NPs). Three different NPs sizes (16, 29 and 45 nm), determined with X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM), were synthesized using a modified Benedict’s reagent. 1H nuclear magnetic resonance (NMR) results show that the hydrolytic degradation of MP leads to the formation of 4-nitrophenol (4-NPh) as the main product. While the P=S bond of MP becomes P=O, confirmed by 31P NMR. Although Cu2O is a widely known photocatalyst, the degradation of methyl parathion was associated to the surface basicity of Cu2O NPs. Indirect evidence for the basicity of Cu2O NPs was achieved through UV–vis absorption of 4-NPh. Likewise, it was shown that the surface basicity increases with decreasing nanoparticle size. The presence of CuCO3 on the surface of Cu2O, identified using X-ray photoelectron spectroscopy (XPS), passivates its surface and consequently diminishes the degradation of MP.

Porphyrins represent a versatile class of molecules, the adsorption behavior of which on solid surfaces is of fundamental interest due to a variety of potential applications. We investigate here the molecule–molecule and molecule–substrate interaction of Co-5,15-diphenylporphyrin (Co-DPP) and 2H-tetrakis(p-cyanophenyl)porphyrin (2H-TCNP) on one bilayer (1BL) and two bilayer (2BL) thick cobalt oxide films on Ir(100) by scanning tunneling microscopy (STM) and density functional theory (DFT). The two substrates differ greatly with respect to their structural and potential-energy landscape corrugation with immediate consequences for adsorption and self-assembly of the molecules studied. On both films, an effective electronic decoupling from the metal substrate is achieved. However, on the 1BL film, Co-DPP molecules are sufficiently mobile at 300 K and coalesce to self-assembled molecular islands when cooled to 80 K despite their rather weak intermolecular interaction. In contrast, on the 2BL film, due to the rather flat potential landscape, molecular rotation is thermally activated, which effectively prevents self-assembly. The situation is different for 2H-TCNPP, which, due to the additional functional anchoring groups, does not self-assemble on the 1BL film but forms self-assembled compact islands on the 2BL film. The findings demonstrate the guiding effect of the cobalt oxide films of different thickness and the effect of functional surface anchoring.

Background Orthogonal T7 RNA polymerase (T7RNAP) and T7 promoter is a powerful genetic element to mediate protein expression in different cells. Among all, Escherichia coli possess advantages of fast growth rate, easy for culture and comprehensive elements for genetic engineering. As E. coli W3110 owns the benefits of more heat shock proteins and higher tolerance to toxic chemicals, further execution of T7-based system in W3110 as cell factory is a conceivable strategy. Results Three novel W3110 strains, i.e., W3110:IL5, W3110::L5 and W3110::pI, were accomplished by chromosome-equipped T7RNAP. At first, the LacZ and T7RNAP with isopropyl-β-D-thiogalactopyranoside (IPTG) induction showed higher expression levels in W3110 derivatives than that in BL21(DE3). The plasmids with and without lacI/lacO repression were used to investigate the protein expression of super-fold green fluorescence protein (sfGFP), carbonic anhydrase (CA) for carbon dioxide uptake and lysine decarboxylase (CadA) to produce a toxic chemical cadaverine (DAP). All the proteins showed better expression in W3110::L5 and W3110::pI, respectively. As a result, the highest cadaverine production of 36.9 g/L, lysine consumption of 43.8 g/L and up to 100% yield were obtained in W3110::pI(−) with plasmid pSU-T7-CadA constitutively. Conclusion Effect of IPTG and lacI/lacO regulator has been investigated in three chromosome-based T7RNAP E. coli strains. The newly engineered W3110 strains possessed similar protein expression compared to commercial BL21(DE3). Furthermore, W3110::pI displays higher production of sfGFP, CA and CadA, due to it having the highest sensitivity to IPTG, thus it represents the greatest potential as a cell factory.

By seeding fungus on top of industry residues, a mycelium can grow and form a compact network structure; however, it may not develop due to lack of optimal nutrients from the substrate. Consequently, peach-palm residues can be a potential alternative; so, to test this hypothesis, this work evaluates the effect of peach-palm residues as substrate for the growth of mycelium based on Lentinula edodes. They were also supplemented with cassava bran and various sources of nitrogen-ammonium sulphate, potassium nitrate, and soy flour—to analyse its effects on its physico-chemical, enzymatic activities, and thermal and mechanical properties of the final composite at 12 and 20 days of cultivation. This mycelium was able to grow at optimum source treatment conditions, which depends on the ratio of Carbon to Nitrogen, within only 12 days of inoculation. Furthermore, the enzyme activities directly correlate with the mycelium growth with optimum conditions of pH, water activity, and moisture for L. edodes to grow having lower enzyme activities for a well-developed composite; whereas higher activities were seen for a weakly developed material, and this material demonstrates mechanical and thermal properties similar to common mycelium-based composites. Therefore, this work demonstrates that peach-palm residues can be a potential alternative for mycelium-based composite.

در این پژوهش حذف آلاینده‌های آلی از آب تولید شده از مخزن گازی پس از جداسازی مواد روغنی مورد بررسی قرار گرفته است، به‌نحوی‌که بتوان COD آن را از مقداری حدود mg/L 9500 به محدوده مجاز آب کشاورزی رساند. در ابتدا با توجه به اینکه هدایت الکتریکی پساب خیلی بالا و در حد µS/cm 6300 است از روش تبخیر جهت کاهش آن استفاده شد که طی این فرآیند هدایت الکتریکی و COD آن به‌ترتیب به µS/cm 1100 و mg/L 750 تقلیل پیدا کرد. با توجه به رسیدن COD پساب به کم‌تر از mg/L 1000 در ادامه از روش فتوالکتروکاتالیست برای تصفیه محصول حاصل از فرآیند تبخیر استفاده شد. در روش فتوالکتروکاتالیست از نانومواد نیمه‌ هادی بور کربن نیترید (BCN) به‌عنوان فتوکاتالیست در میکروراکتور نوع سیم پیچی با نسبت سطح به حجم بالا در حدود 3 m2/m 3000 استفاده شد که همین امر باعث اکسیداسیون سریع مواد آلی می‌شود. پس از ساختن میکروراکتور، تأثیر پارامترهای مختلف بر میزان حذف COD مورد بررسی قرار گرفت که مشخص شد بیشترین میزان حذف COD در 3=pH، اختلاف پتانسیل V 20 و هدایت الکتریکی µS/cm 2500 به‌دست می‌آید (80%) که طی آن COD به mg/L 150 کاهش یافته که مناسب برای آبیاری و کشاورزی است.

The application of nanoparticle in medicine is promising for the treatment of a wide variety of diseases. However, the slow progress in the field has resulted in relatively few therapies being translated into the clinic. Anisotropic synthetic protein nanoparticles (ASPNPs) show potential as a next-generation drug-delivery technology, due to their biocompatibility, biodegradability, and functionality. Even though ASPNPs have the potential to be used in a variety of applications, such as in the treatment of glioblastoma, there is currently no high-throughput technology for the processing of these particles. Insulator-based electrokinetics employ microfluidics devices that rely on electrokinetic principles to manipulate micro- and nanoparticles. These miniaturized devices can selectively trap and enrich nanoparticles based on their material characteristics, and subsequently release them, which allows for particle sorting and processing. In this study, we use insulator-based electrokinetic (EK) microdevices to characterize ASPNPs. We found that anisotropy strongly influences electrokinetic particle behavior by comparing compositionally identical anisotropic and non-anisotropic SPNPs. Additionally, we were able to estimate the empirical electrokinetic equilibrium parameter (eEEEC) for all SPNPs. This particle-dependent parameter can allow for the design of various separation and purification processes. These results show how promising the insulator-based EK microdevices are for the analysis and purification of clinically relevant SPNPs.

Cyanobacteria and Spirulina produce C-phycocyanin (CPC), a water soluble protein associated pigment, which is extensively used in food and pharmaceutical industries. Other therapeutic proteins might exist in microalgal cells, of which there is limited knowledge. Such proteins/peptides with antibiotic properties are crucial due to the emergence of multi-drug resistant pathogens. In addition, the native expression levels of such disease resistant proteins are low, hindering further investigation. Thus, screening and overexpression of such novel proteins is urgent and important. In this study, a protein which was identified as a putative disease resistance protein (DRP) in the mixture of Spirulina product has been explored for the first time. To improve protein expression, DRP was cloned in the pET system, co-transformed with pRARE plasmid for codon optimization and was significantly overexpressed in E. coli BL21(DE3) under induction with isopropyl-β-d-1-thiogalactopyranoside (IPTG). Furthermore, soluble DRP exhibited intense antimicrobial activity against predominant pathogens, and an inhibition zone of 1.59 to 1.74 cm was obtained for E. coli. At a concentration 4 mg/mL, DRP significantly elevated the growth of L. rhamnosus ZY up to twofold showing probable prebiotic activities. Moreover, DRP showed potential as an effective antioxidant, and the scavenging ability for ROS was in the order of hydroxyl > DPPH > superoxide radicals. A putative disease resistance protein (DRP) has been identified, sequenced, cloned and over-expressed in E. coli as a functional protein. Thus expressed DRP showed potential anti-microbial and antioxidant properties, with promising therapeutic applications.

Traditional transparent conducting oxides (TCOs) have been widely used for various optoelectronic applications, but have the trade-off between conductivity and transmittance. Recently, perovskite oxides, with structural and chemical stability, have exhibited excellent physical properties as new TCOs. We focus on SrVO3-based perovskites with a high carrier concentration and BaSnO3-based perovskites with a high mobility for n-type TCOs. In addition, p-type perovskites are discussed, which can serve as potential future options to couple with n-type perovskites to design full perovskite based devices.

Nanofibrous materials have great potential for use in tissue engineering due to their structure, which mimics the extracellular fibrous matrix. Increasing their biological activity is currently the main goal in the development of these scaffolds. From the standpoint of promoting healing and tissue regeneration, the use of human platelets containing hundreds of biologically active molecules is promising. The present work deals with the preparation of PVA-based nanofibrous material containing native platelet-derived proteins that are released in a sustained manner. The needleless electrospinning process of preparation of material that does not affect the activity of incorporated proteins has been optimized, and the resulting material can be produced on a large scale with a protein loading efficiency of 0.64%. The reasonable fiber diameter distribution (370±150 nm) with low defects ensures a homogeneous distribution of proteins. The use of high molecular weight PVA (125000 g/mol) with a high degree of hydrolysis (98–98.8%) resulted in a 40% reduction in PVA solubility without the need for subsequent covalent crosslinking. This, in turn, results in a sustained release of proteins, where after an initial burstrelease of 90% of the proteins, 10% is gradually released over the next 7 days. Our results demonstrate the potential use of the platelet-lysate loaded PVA material in tissue engineering.

در این مطالعه، ابتدا از 8- هیدروکسی کینولین برای سنتز نانوذرات FeQ3 و اصلاح نانوذرات آهن اکسید (Fe3O4) استفاده شد. سپس نانوذرات سنتزی FeQ3 و نانوذرات اصلاح شده آهن (HQ-Fe3O4) برای ساخت غشاهای نانوفیلتراسیون مورد استفاده قرار گرفتند. بنابراین با استفاده از غلظت‌های مختلف نانوذرات به‌عنوان افزودنی در پلی اتر- سولفون (PES)، غشاهای نانوفیلتراسیون PES/FeQ3 و PES/HQ-Fe3O4 ساخته شدند. جهت ارزیابی پیوندهای شیمیایی تشکیل شده در نانوذرات سنتز شده FeQ3، نانوذرات اصلاح شده HQ-Fe3O4 و غشاها از آنالیز FTIR استفاده شد. همچنین جهت ارزیابی مورفولوژی ساختار غشاهای آماده شده از آنالیزهای SEM و AFM استفاده شد. سپس عملکرد جداسازی و فیلتراسیون غشاهای ساخته شده، توسط شار آب خالص عبوری و جداسازی نمک‌های منیزیم سولفات ارزیابی شد. نتایج، بالاترین میزان شار آب خالص غشاهای تهیه شده PES/FeQ3 و PES/HQ-Fe3O4 را L/m2h 6/17 برای غشای محتوی 5/0% وزنی از نانوذرات نشان داد؛ درحالی‌که شار آب خالص برای غشای خالص پلی اتر سولفون (بدون نانوذره) حدود L/m2h 1/7 بود. همچنین، میزان دفع منیزیم سولفات برای غشای محتوی نانوذرات FeQ3 به حدود 86% در 5/0% وزنی از نانوذرات افزایش یافت و برای غشای PES/HQ-Fe3O4 به 91% در 5/0% وزنی از نانوذرات اصلاح شده افزایش پیدا کرد درحالی‌که میزان آن برای غشای خالص بدون نانوذره 55/58% بود. همچنین، ارزیابی شار نسبت به زمان نشان داد که غشاهای اصلاح شده نسبت به غشای خالص دارای عملکرد جداسازی قابل توجهی هستند.

Hexanol–butanol–ethanol fermentation from syngas by Clostridium carboxidivorans P7 is a promising route for biofuel production. However, bacterial agglomeration in the culture of 37 °C severely hampers the accumulation of biomass and products. To investigate the effect of culture temperature on biomass growth and higher-alcohol production, C. carboxidivorans P7 was cultivated at both constant and two-step temperatures in the range from 25 to 37 °C. Meanwhile, Tween-80 and saponin were screened out from eight surfactants to alleviate agglomeration at 37 °C. The results showed that enhanced higher-alcohol production was contributed mainly by the application of two-step temperature culture rather than the addition of anti-agglomeration surfactants. Furthermore, comparative transcriptome revealed that although 37 °C promoted high expression of genes involved in the Wood–Ljungdahl pathway, genes encoding enzymes catalyzing acyl-condensation reactions associated with higher-alcohol production were highly expressed at 25 °C. This study gained greater insight into temperature-effect mechanism on syngas fermentation by C. carboxidivorans P7.

یکی از راه‌های جلوگیری از گرم شدن کره زمین و افزایش ارزش حرارتی گاز طبیعی، جذب کربن دی اکسید و نیتروژن، با استفاده از زئولیت‌ها است. در این مطالعه، نتایج تجربی جذب سه گاز متان، کربن دی اکسید و نیتروژن توسط زئولیت 13X، با استفاده از شبکه عصبی مصنوعی مورد بررسی قرار گرفت. دما و فشار به‌عنوان ورودی‌های سیستم و ظرفیت جذب به‌عنوان خروجی در نظر گرفته شد. در همه مدل‌ها از الگوریتم پس انتشار لونبرگ- مارکوآرت برای آموزش شبکه استفاده شد. جهت تعیین توابع انتقال بهینه در لایه‌های پنهان و خروجی و نرون بهینه از شاخص‌های ضریب تعیین، خطای میانگین مربعات، مجموع خطاهای مربع و خطای میانگین مربع ریشه استفاده شد. نرون بهینه برای متان، کربن دی اکسید و نیتروژن به‌ترتیب 10، 10 و 15 به‌دست آمد. همچنین بهترین نتایج برای توابع انتقال، Logsig و Tansig برای متان، Logsig و Purelin برای کربن دی اکسید و نیتروژن به‌ترتیب برای لایه پنهان و لایه خروجی به‌دست آمدند. ضریب تعیین در شرایط بهینه برای متان، کربن دی اکسید و نیتروژن به‌ترتیب 9970/0، 9842/0 و 9937/0 به‌دست آمد. در پایان درصد انحراف میانگین برای نتایج پیش‌بینی شده توسط شبکه عصبی با نتایج توسط مدل لانگمویر و مدل Sips وابسته به دما مقایسه شد که نشان از دقت بالای شبکه عصبی مصنوعی نسبت به دو مدل است.

از آنجایی‌که در اکتشاف و تولید نفت به مطالعات ژئومکانیک مخزن توجه ویژه‌ای دارند، در این پژوهش تأثیر رخساره، محیط رسوبی، بافت و دیاژنز بر رفتار ژئومکانیکی سازند آسماری بررسی شده است. داده‌های استفاده شده شامل 1) داده‌های رسوب‌شناسی مانند پتروگرافی مقطع نازک، تخلخل و چگالی؛ 2) داده‌های مکانیک سنگ مانند مقاوت تراکمی تک‌محوری و سه‌محرری سنگ، ضریب چسبندگی و زاویه اصطکاک داخلی سنگ، مقاومت کششی سنگ و اندیس شکستگی و حفاری؛ 3) داده‌های سرعت موج S و P. که برروی 140 عدد مغزه رخنمون و چاه انجام شدند. به‌منظور مطالعه رابطه ممکن بین خصوصیات رسوب‌شناسی و مکانیکی سنگی، خصوصیات رسوب شناسی با اندیس رخساره براساس ویژگی‌های بافتی و دیاژنزی رقومی شده‌اند. براساس اندیس رخساره، مقدار تخلخل و مقاومت تراکمی تک محوری سنگ پنج رخساره ژئومکانیکی در سازند آسماری مشخص شد که از رخساره ژئومکانیکی 1 تا 5 از رفتار شکل‌پذیر به شکننده تبدیل می‌شوند. نتایج این مطالعه نشان می‌دهد که رفتار مکانیکی سنگ توسط محیط رسوبی و فرآیندهای دیاژنزی کنترل می‌شود که با رقومی کردن خصوصیات رسوب‌شناسی و ایجاد ارتباط با پارامترهای مکانیک سنگی امکان پیش‌بینی مقاومت تراکمی تک محوری سنگ با استفاده از پتروگرافی ایجاد شده است. چنین مطالعاتی کمک موثری در کاهش وقت و هزینه آزمایشات مکانیک سنگ و همچنین در منطقه‌بندی مکانیکی- چینه‌ای مخزن دارد.

The past few decades have witnessed an upsurge in the utilization of natural fibres in green materials advancement. This rise can be linked to calls from stakeholders, around the world, on the issue of sustainability and eco-friendliness. A shift from the utilization of non-biodegradable sources to renewable sources is a current area of intense research, which also stimulates industrial attention. Amongst the creations of nature, silkworm silk fibres have attracted considerable interest from materials science researchers. Inferable from its amazing biocompatibility, bioresorbability, and biodegradability, silkworm silk strands have been used in the improvement of polylactic acid/silk fibre biocomposites. Hence, with the continued use of these biocomposites in industrial and biomedical applications, it has become necessary to look at the systematic progress made in its processing, overall property improvements, and various applications. This review article also presents the challenges facing the advancement of this biocomposite, the suggested solutions and concludes with anticipated future trends.

The oxidation of Au/Ag alloy thin films using radio-frequency oxygen plasma was studied in this work. It was demonstrated that there is a phase separation occurring between silver and gold. In addition, it was shown that the preferential oxidation of silver resulted in a solid-state diffusion of silver toward the surface where it oxidized and formed nanoporous microspheres. The gold phase remaining in the film exhibited nanoporosity due to the injected vacancies at the metal/silver oxide interface. Based on the scanning transmission electron microscopy analysis coupled with energy dispersive X-ray mapping a mechanism was proposed based on solid-state diffusion and the Kirkendall effect to explain the different steps occurring during the oxidation process.

جذب و ته‌نشست آسفالتین بر سطح منافذ سنگ مخزن موجب تغییر خواص سنگ از جمله تراوایی، تخلخل و ترشوندگی و در نتیجه، آسیب سازند می‌شود. نانوذرات دارای پتانسیل لازم برای جذب و ممانعت از تشکیل رسوب آسفالتین هستند. در این تحقیق، نانوذرات به‌صورت درجا در نفت سنتز شد و امکان‌سنجی کنترل آسیب آسفالتین در مغزه‌های کربناته کم‌تراوا در حضور این نانوذرات بررسی گردید. بدین منظور، ابتدا نفت مدل از انحلال نفت مرده در مخلوط تولوئن/ گازوئیل تهیه شد و سپس امولسیون‌های پایدار محلول آبی نمک نیترات آهن در نفت مدل ساخته شد. این امولسیون‌ها در دمای مخزن و فشارهای مختلف قرار گرفتند تا نانوذرات به‌صورت درجا سنتز ‌شوند. ساختار کریستالی، توزیع اندازه و ریخت‌شناسی این نانوذرات خودسنتزشو و همچنین، ظرفیت جذب مواد هیدروکربنی بر سطح آنها بررسی شد. نهایتاً دو مغزه کربناته کم‌تراوا با اندیس زون جریانی مشابه انتخاب شد و با انجام آزمایش سیلاب‌زنی مغزه‌ها و ثبت تغییرات تراوایی مؤثر هیدروکربنی، اثرات نانوذرات سنتزی بر کنترل آسیب سازند بررسی گردید. در آزمایش سیلاب‌زنی، یکی از مغزه‌ها‌ با نفت مدل و مغزه دوم با امولسیون آب نمک نیترات آهن در نفت مدل اشباع شدند و القاء آسیب آسفالتین با تزریق نرمال هگزان انجام شد. تغییرات تراوایی مؤثر سیکلوهگزان قبل و بعد از القاء آسیب به‌عنوان معیاری از شدت آسیب سازند ثبت گردید. نتایج آنالیزهای XRD و FESEM به‌ترتیب نشان از ساختار کریستالی نانوذرات سنتزی و متوسط اندازه nm 65 دارند که از قطر منافذ مؤثر مغزه‌ها کوچک‌تر است. آزمایش‌های سیلاب‌زنی نشان می‌دهند که با افزایش افت فشار تخلیه، که با دبی تزریق/ تولید بالا همراه است، هرچند میزان کاهش تراوایی ناچیز است ولی سنتز در جای نانوذرات در کنترل آسیب سازند مؤثر است. اما در دبی تزریق/ تولید پایین، سنتز در جای نانوذرات می‌تواند از طریق به تله افتادگی قطرات آبی باعث کاهش هرچه بیشتر تراوایی مؤثر فاز هیدروکربنی گردد.

Based on an electrochemical method, three-dimensional arrayed nanopore structures are machined onto a Mg surface. The structured Mg surface is coated with a thin gold (Au) film, which is used as a surface-enhanced Raman scattering (SERS) substrate. A rhodamine 6G (R6G) probe molecule is used as the detection agent for the SERS measurement. Different sizes of arrayed micro/nanostructures are fabricated by different treatment time using the electrochemical process. The topographies of these micro/nanostructures and the thickness of the Au film have an influence on the Raman intensity of the Mg substrate. Furthermore, when the thickness of Au film coating is held constant, the Raman intensity on the structured Mg substrates is about five times higher after a treatment time of 1 min when compared with other treatment times. The SERS enhancement factor ranges from 106 to 1.75 × 107 under these experimental conditions. Additionally, a 10−6 mol·L−1 solution of lysozyme was successfully detected using the Mg–Au nanopore substrates. Our low-cost method is reproducible, homogeneous, and suitable for the fabrication of SERS substrates.

تولید ماسه سازندی یکی از چالش‌های اساسی شرکت‌های بهره‌بردار در عملیات تکمیل و تولید از چاه‌های نفتی و گازی است. با توجه به آنکه در اکثر موارد، تولید ماسه امری اجتناب‌ناپذیر است، انتخاب روش مناسب کنترل ماسه و طراحی تکمیل چاه، موضوعی بسیار ضروری و کلیدی تلقی می‌شود و از جمله روش‌های بهبود تولید و افزایش بهره‌وری محسوب می‌گردد. بنابراین آنالیز و بررسی شرایط تولید ماسه و عوامل تأثیرگذار بر انتخاب هر روش کنترل تولید ماسه، دارای اهمیت فراوان در پایداری تولید می باشند که در این مطالعه با رویکردی داده محور مورد توجه قرار گرفته است. این مطالعه با تمرکز بر روش‌های داده محور، از تکنیک شباهت به راه حل ایده‌آل (الگوریتم تاپسیس) -به عنوان یکی از روش‌های تصمیم‌گیری چند معیاره- برای غربال‌گری مخازن نفتی جنوب غرب ایران که با مشکل تولید ماسه مواجه هستند، استفاده می‌کند. در این کار، با استفاده از اطلاعات چاه‌های با مشکل تولید ماسه در دو میدان نفتی جنوب غرب ایران، مقدار ایده‌آل هر یک از معیار‌های مؤثر بر انتخاب سامانه مناسب مهار ماسه، استخراج شده است. سپس با به‌کارگیری روش تاپسیس در مسائل تصمیم‌گیری چند معیاره، به رتبه‌بندی روش‌های ‌مهار ماسه برای چاه‌های نفتی مورد مطالعه پرداخته شده است. نتایج نشان می دهد که جهت مهار ماسه، استفاده از روش رزین و آروماتیک در اولویت اول و روش‌های آستری شیار دار، توری انبساط‌پذیر، رزین و بستر شنی به ترتیب در رتبه‌های دوم تا پنجم قرار می‌گیرند.

A commercially available methylphenylvinylhydrogen polysiloxane preceramic polymer was cross-linked and pyrolyzed in argon in order to study if this compound could be used as an organic precursor for the manufacture of silicon carbide parts by photopolymerisation-based three-dimensional printing. X-Ray diffraction experiments and transmission electron microscopy observations showed that the pyrolyzed material was constituted by an interconnected polycrystalline network made of faulted/twinned &beta, SiC grains surrounded by an amorphous and porous second phase mainly constituted (at least 80 at%) of carbon. The free carbon residual content was estimated to be around 17.2 wt%. Additional efforts are then required to be able to use such a preceramic polymer to manufacture SiC parts by photopolymerisation-based three-dimensional printing.