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n this study Mn-DABDC (DABDC = diaminobenzenedicarboxylate, or 2,5-diaminoterephthalate) MOF was synthesized via an electrochemical method, and a Mn-BDC (BDC = benzenedicarboxylate) MOF was also prepared by a conventional solvothermal method for gas uptake capacity comparison. Investigation of the synthesis parameters demonstrated that current density, electrolyte amount and reaction time were the most significant factors affecting crystal synthesis and product yield. The best conditions found for obtaining crystalline MOF with high yield (93%) were 70 mA current, electrolyte 2.7 mmol / 30 ml DMF and 2 hrs of reaction time. These optimized electrochemical conditions allow for a relatively fast MOF synthesis, important for reducing synthesis cost compared with conventional hydrothermal and solvothermal methods. The Mn-DABDC MOF sample was fully characterized to analyse its structure, thermal stability and surface area. The electrochemically synthesized MOF has high carbon dioxide uptake (92.4 wt% at 15 bar and 273 K) and hydrogen uptake (12.3 wt% at 80 bar pressure and 77 K). This is the first amine-based manganese MOF synthesized electrochemically, and the method has excellent potential for reducing large-scale MOF production costs.

Multidentate 1,3,5-benzene tricarboxylic acid copolymerizes with Zinc to form framework with rigid porosity for gas adsorption application. One of the barriers in commercialization of these MOFs for gas adsorption application is the usage of costly solvents and this research is based on identifying the effect of solvents on zinc and 1,3,5-benzene tricarboxylic acid-based MOFs, their gas adsorption capacities and costs. All the MOFs prepared were characterized and further tested for carbon dioxide adsorption capacities. The results highlight that the textural properties of prepared MOFs depend largely on solvents utilized and high surface area MOFs have high adsorption capacity. Also the carbon dioxide adsorption capacity of MOFs prepared using DMF showed better adsorption as compared with the one prepared with Ethanol:De-ionized water. This research also elaborates the fact that there is a possibility of replacing the expensive solvents for Zn-BTCs synthesis with low-cost solvents without compromising the gas adsorption performance.

The continuous carbon dioxide (CO2 ) gas emissions associated with fossil fuel production, valorization, and utilization are serious challenges to the global environment. Therefore, several developments of CO2 capture, separation, transportation, storage, and valorization have been explored. Consequently, we documented a comprehensive review of the most advanced strategies adopted in metal-organic frameworks (MOFs) for CO2 capture and separation. The enhancements in CO2 capture and separation are generally achieved due to the chemistry of MOFs by controlling pore window, pore size, open-metal sites, acidity, chemical doping, post or pre-synthetic modifications. The chemistry of defects engineering, breathing in MOFs, functionalization in MOFs, hydrophobicity, and topology are the salient advanced strategies, recently reported in MOFs for CO2 capture and separation. Therefore, this review summarizes MOF materials' advancement explaining different strategies and their role in the CO2 mitigations. The study also provided useful insights into key areas for further investigations.

The continuous carbon dioxide (CO

Introduction: Cervical cancer is a prevalent malignancy that has a high death and morbidity rate. It's caused by aberrant cell proliferation with the capacity to infiltrate and spread to other portions of the body. Objective: The main objective of the study is to compare the degree of agreement between MRI and histopathology in T staging of cervical carcinoma. Material and Methods: This cross sectional study was conducted in the department of radiology, Mayo Hospital Lahore for 6 months i.e. 12 Feb 2019 to 11 Feb 2020. MRI of the pelvis performed using a 1.5 tesla MRT 1580 scanner. All the results were interpreted by our senior radiologist and T-stage was noted according to MRI findings. All histopathological examinations performed. Both MRI and histopathology were separately place. Results: The mean age of patients was 46.45±13.38 years, 25(25%) patients were with underweight BMI and obese BMI patients were 36(36%). In our study the agreement between the MRI and histopathology was found in 77(77%) patients. Conclusion: According to our study results the MRI had good agreement with histopathology in T staging of cervical carcinoma.

It is well recognized fact that materials properties depend up on synthesis technique. We cause this power for changing physical and chemical properties of materials. Metal organic frameworks are porous coordination polymers that have highly porous structure, great surface area and can be utilized for gas capturing and storage applications. Improving MOFs surface area have always been aimed in coordination chemistry. Synthesis reactions need mass physical forces where mass transfer of reactants is required, and it can definitely be provided by sonochemical synthesis approach. In this study BDC linker-based MOFs were-synthesized using ultrasonication method. Prepared sample was activated under vacuum to obtain highly porous MOF crystals. All prepared samples were fully characterized using PXRD, TGA, SEM-EDS and BET analysis. Results indicated Mn-BDC MOF has highest carbon dioxide capturing tendency.

Herein we report a facile, efficient, low cost, and easily scalable route for an amine-functionalized MOF (metal organic framework) synthesis. Cu-BDC&sup, HMTA (HMTA = hexamethylenetetramine) has high nitrogen content and improved thermal stability when compared with the previously reported and well-studied parent Cu-BDC MOF (BDC = 1,4-benzenedicarboxylate). Cu-BDC&sup, HMTA was obtained via the same synthetic method, but with the addition of HMTA in a single step synthesis. Thermogravimetric studies reveal that Cu-BDC&sup, HMTA is more thermally stable than Cu-BDC MOF. Cu-BDC&sup, HMTA exhibited a CO2 uptake of 21.2 wt % at 273 K and 1 bar, which compares favorably to other nitrogen-containing MOF materials.

It is well recognised fact that the properties of materials depend on the synthesis technique. We can use this power to change the physical and chemical properties of materials. Metal organic frameworks are porous coordination polymers that have a highly porous structure, great surface area and can be utilised for gas capturing and storage applications. Improving the surface area of MOFs has always been targeted in coordination chemistry. Synthesis reactions need mass physical forces where the mass transfer of reactants is required, and it can definitely be provided by the sonochemical synthesis approach. In this study, the very well-known MOF-2 was re-synthesised using an ultrasonication method. The prepared sample was activated under vacuum to obtain highly porous MOF crystals. All the prepared samples were fully characterized using SCXRD, PXRD, FTIR TGA, SEM-EDS and BET analysis. The results indicated highly crystalline, water stable MOF materials with a high carbon dioxide capture tendency. Moreover, it was found that sonication treatment and vacuum activation at high temperature increases the specific surface area of the prepared samples compared to MOF-2 prepared by a conventional solvothermal synthesis.

Reducing carbon dioxide levels in atmosphere presents greatest challenge in controlling global climate change. Each stage of Carbon Capture and Storage (CCS) strategy requires specialized materials. Metal–organic framework, being highly porous and crystalline materials are captivating vast scientific attention for exploring their potential in gas adsorption applications. This research work presents an attempt to synthesis post amine modified MOF materials for enhanced carbon dioxide capture applications. Thermogravimetic studies reveal that EDA MOF-5 is far more thermally stable then MOF-5; moreover synthesis can be performed successfully with recycled solvent (DMF). Carbon dioxide adsorption studies represents better carbon dioxide capture tendency for MOF-5 and EDA MOF-5 i.e., 5 mmol/g and 3.9 mmol/g respectively at 0°C.

Metal–organic frameworks (MOFs) based on 2,5-dihydroxyterepthalic acid (DOBDC) as the linker show very high CO 2 uptake capacities at low to moderate CO 2 pressures; however, these MOFs often require expensive solvent for synthesis and are difficult to regenerate. We have synthesized a Mn-DOBDC MOF and modified it to introduce amine groups into the structure by functionalizing its metal coordination sites with ethylenediamine (EDA). Repeat framework synthesis was then also successfully performed using recycled dimethylformamide (DMF) solvent. Characterization by elemental analysis, FTIR and thermogravimetric studies suggest that EDA molecules are successfully substituting the original metal-bound DMF. This modification not only enhances the material's carbon dioxide sorption capacity, increasing stability to repeated CO 2 sorption cycles, but also improves the framework's stability to moisture. Moreover, this is one of the first amine-modified MOFs that can demonstrably be synthesized using recycled solvent, potentially reducing the future costs of production at larger scales.

In this study, the efficiency of alum sludge for removing phosphorus from synthetic and municipal wastewater (MWW) was investigated. Orthophosphorus (OP) and condensed phosphorus (CP) were used as model pollutants. Alum sludge (A and B) from two local treatment plants was collected, dewatered, dried, and processed before use. Batch experiments were performed to determine OP and CP removal under equilibrium conditions. Sludge dose, contact time, and pH were optimized for both sludges. Adsorption efficiencies of OP and CP were determined by using Langmuir and Freundlich adsorption isotherm models. The maximum adsorption capacity (Qo) for sludge A was found to be 4.86 mg/g for OP, and 4.21 mg/g for CP at 12 g/L of sludge dose, 90 min of contact time, and pH 4. For sludge B, Qo was 1.58 mg/g for OP and 4.71 mg/g for CP at 30 g/L of sludge dose, 80 min of contact time, and pH of 5.5. Results showed that pH of wastewater significantly affected adsorption capacity and better removal was achieved within p...

This study stemmed from consumer complaints about earthy and musty off-flavours in treated water of Rawal Lake Filtration Plant. In recent years, several novel adsorbents have been developed from nanomaterials for enhancing the contaminant removal efficiency. This paper presents preparation and the use of new adsorbents Pt doped titania and Fe doped titania, for the adsorption capacity of Geosmin and 2-MIB from water under laboratory conditions and their comparison, with most widely used activated carbon, under batch and column experiments. Stock solutions were prepared by using Geosmin and 2-MIB standards, procured by Sigma Aldrich (England). Samples were analysed using SPME-GC-FID. The adsorption of Geosmin and 2-MIB on GAC conformed to the Freundlich isotherm, while that of adsorption on metal doped titania fit equally well to both Langmuir and Freundlich isotherms. Moreover, data, generated for the kinetic isotherm, confirmed that Geosmin and 2-MIB removal is a function of contact time. Breakthrough column tests using 125 mg/L Pt doped titania nanoparticles, coated on glass beads against 700 ng/L of off-flavours, attained later breakthrough and exhaustion points and removed 98% of Geosmin and 97% of 2-MIB at room temperature. All columns could be regenerated using 50 mL 0.1 molar sodium hydroxide.