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Conjugated microporous polymers (CMPs) are a prospective class of porous materials that are promising in a wide variety of applications due to their outstanding physical and chemical properties.

Heavy metal ions removal from wastewater has attracted keen interest due to its toxicity. Adsorption is one of the most promising approaches for heavy metal ions removal owing to its simplicity and effectiveness. Recently, covalent organic frameworks (COFs) have become promising adsorbents for effective wastewater remediation. However, many building blocks have been developed, and the constructing COFs with high adsorption efficiency remains a challenge. Herein, covalent organic framework, DHTP–TPB COF, decorated with hydroxyl groups was designed for the efficiency Pb2+ removal. The DHTP–TPB COF showed excellent performance in adsorbing Pb2+ from aqueous solution. More importantly, DHTP-TPB COF shows a high selectivity for Pb2+ compared to other competing ions, which captured Pb2+ ions with a removal efficiency of over 96% at pH ~ 4. The results show that the DHTP–TPB COF has excellent adsorption capacity at pH 4 up to 154.3 mg/g for Pb2+ ions, the value is comparable with many COFs reported so far. More interestingly, this work provided a correction to the way of the isotherm study that has been frequently followed before. Moreover, the adsorbed Pb2+ ions could be readily eluted using a 0.1M EDTA solution, and the DHTP–TPB COF can be reused for more than five adsorption-elution cycles without any significant adsorption efficiency loss. Furthermore, the adsorption mechanism was revealed using the XPS analysis indicating the formation of strong coordination bonding interactions between hydroxyl and Pb2+. Therefore, the DHTP–TPB COF produced herein has a high potential for treating Pb2+-contaminated wastewater, and it is promising for Pb2+ ion adsorption in practice.

This study was conducted to assess the bioactive value of Tamarix gallica honey samples collected from three countries. In total, 150 Tamarix gallica honey samples from Saudi Arabia (50), Libya (50), and Egypt (50) were collected and compared, based on the results of the melissopalynological analysis, their physicochemical attributes, antioxidant and antimicrobial activities, and biochemical properties, together with their total phenolic and total flavonoid contents. Depending on the geographical origin, we observed different levels of growth suppression for six resistant bacterial strains. The pathogenic microorganisms tested in this study were Staphylococcus aureus, Streptococcus mutans, Klebsiella pneumoniae, Escherichia coli, Proteus vulgaris, and Pseudomonas aeruginosa. There was a strong correlation between the polyphenol and flavonoid contents, as well as significant (p < 0.05) radical scavenging activities. The melissopalynological analysis and physicochemical properties complied with the recommendation of the Gulf and Egyptian Technical Regulations on honey, as well as the Codex Alimentarius of the World Health Organization and the European Union Normative related to honey quality. It was concluded that Tamarix gallica honey from the three countries has the capacity to suppress pathogenic bacterial growth and has significant radical scavenging activities. Moreover, these findings suggest that Tamarix gallica honey may be considered as an interesting source of antimicrobial compounds and antioxidants for therapeutical and nutraceutical industries or for food manufacturers.

An efficient and metal-free approach to the synthesis of new kinds of CMPs (pyrrolo[3,2-b]pyrrolyl-based CMPs) on a gram scale within a short time has been developed for remarkable adsorbent and photocatalytic degradation of organic pollutants.

The higher the polarity or the hydrogen bond donor ability of the solvent, the more easily COFs crystallize, and the higher the COF crystallization, the higher the photocatalytic H2 evolution.

2D Ag2SO4 nanosheets have been delaminated from bulk Ag2S using a two-step combined exfoliation method. Upon blue light irradiation, the 2D Ag2SO4-based sensor exhibits high-performance responses toward low-concentrated NO2 gas at room temperature.

Background Since December 2019, Covid-19 has resulted in high morbidity and mortality worldwide. MIS-C associated with SARS-CoV-2 infection led to serious and life-threatening illness in children causing severe multisystem inflammation. It presented with new neurological symptoms involving both the central and peripheral nervous systems. The aim is to evaluate the neurological manifestations in pediatric patients with MIS-C associated to COVID-19. Aim To evaluate the neurological manifestations in Pediatric Patients with Multisystem Inflammatory Syndrome in Children (MIS-C) associated to COVID-19. Methods This cross section study included patients who were admitted to Pediatric Intensive Care Unit (PICU) isolation unit at Minia University Hospital during the period from December 2020 to April 2022. The study included a total of 303 patients who were classified in to 3 groups; Group (I) (MIS-C, PCR positive), Group (II) (MIS-C, PCR negative), and Group (III) (Non-MIS-C, PCR positive). Results The respiratory, cardiovascular, hematologic and gastrointestinal symptoms were significantly greater among Group (II). Convulsions, DCL, Headache, and Weakness were significantly more demonstrated in Group (I) (19 (31.7%), 17 (28.3%), 17 (28.3%), and 15 (25.0%), respectively). While, drowsiness was significantly more demonstrated in Group (II) (41 (21.9%)). Lymphocytes (%) showed significant lower values in Group (I) and Group (II) (Mean ± SD is 18.9 ± 1.8(, compared to Group (III) (Mean ± SD is 21.4 ± 1.8), p-value

Herein we report the rational syntheses of three conjugated microporous polymers (CMPs) through one-pot polycondensation couplings of a boronated triphenylpyridine (TPP-3Bor) with 4,7-bis(5-bromothien-2-yl)benzo[c][1,2,5]thiadiazole (ThZ-2Br), 2,5-dibromothiophene (Th-2Br), and 1,4-dibromobenzene (Bz-2Br), yielding...

The efficient and selective photocatalytic CO

In this study, we prepared a difunctionalized cyanate ester double-decker silsesquioxane (DDSQ-OCN) cage with a char yield and thermal decomposition temperature (Td) which were both much higher than those of a typical bisphenol A dicyanate ester (BADCy, without the DDSQ cage) after thermal polymerization. Here, the inorganic DDSQ nanomaterial improved the thermal behavior through a nano-reinforcement effect. Blending the inorganic DDSQ-OCN cage into the epoxy resin improved its thermal and mechanical stabilities after the ring-opening polymerization of the epoxy units during thermal polymerization. The enhancement in the physical properties arose from the copolymerization of the epoxy and OCN units to form the organic/inorganic covalently bonded network structure, as well as the hydrogen bonding of the OH groups of the epoxy with the SiOSi moieties of the DDSQ units. For example, the epoxy/DDSQ-OCN = 1/1 hybrid, prepared without Cu(II)-acac as a catalyst, exhibited a glass transition temperature, thermal decomposition temperature (Td), and char yield (166 °C, 427 °C, and 51.0 wt%, respectively) that were significantly higher than those obtained when applying typical organic curing agents in the epoxy resin. The addition of Cu(II)-acac into the epoxy/BADCy and epoxy/DDSQ-OCN hybrids decreased the thermal stability (as characterized by the values of Td and the char yields) because the crosslinking density and post-hardening also decreased during thermal polymerization; nevertheless, it accelerated the thermal polymerization to a lower curing peak temperature, which is potentially useful for real applications as epoxy molding compounds.

The removal of heavy metal ions from wastewater has attracted considerable interest because of their toxicity. Adsorption is one of the most promising methods for the removal of heavy metal ions due to its simplicity and effectiveness. Recently, covalent organic frameworks (COFs) have become promising adsorbents for effective wastewater remediation. However, many building blocks have been developed, and the design of COFs with high adsorption efficiency remains a challenge. Here, a covalent organic framework (DHTP-TPB COF) decorated with hydroxyl groups was developed for the efficient removal of Pb

Herein, we report the efficient preparation of π-electron-extended triazine-based covalent organic framework (TFP-TPTPh COF) for photocatalysis and adsorption of the rhodamine B (RhB) dye molecule, as well as for photocatalytic hydrogen generation from water. The resultant TFP-TPTPh COF exhibited remarkable porosity, excellent crystallinity, high surface area of 724 m2 g−1, and massive thermal stability with a char yield of 63.41%. The TFP-TPTPh COF demonstrated an excellent removal efficiency of RhB from water in 60 min when used as an adsorbent, and its maximum adsorption capacity (Qm) of 480 mg g−1 is among the highest Qm values for porous polymers ever to be recorded. In addition, the TFP-TPTPh COF showed a remarkable photocatalytic degradation of RhB dye molecules with a reaction rate constant of 4.1 × 10−2 min−1 and an efficiency of 97.02% under ultraviolet–visible light irradiation. Furthermore, without additional co-catalysts, the TFP-TPTPh COF displayed an excellent photocatalytic capacity for reducing water to generate H2 with a hydrogen evolution rate (HER) of 2712 μmol g−1 h−1. This highly active COF-based photocatalyst appears to be a useful material for dye removal from water, as well as solar energy processing and conversion.

The study aimed to identify the concept, characteristics and advantages of the transition to a green economy and its relationship with the Egyptian banking system. Green over the coming years. The study concluded that the green economy is the best way to preserve the environment and stimulate economic growth and eradicate poverty. There is a positive relationship between the volume of credit in the banking system and the volume of credit directed to green projects. The researcher made several recommendations, the most important of which are: The need for banks to establish special systems to finance green projects commensurate with the nature of these projects and the establishment of new banking products in the so-called (green banking). Appropriate, with the establishment of a new specialized department to monitor the credit risk of green projects and take appropriate measures to detect any risks that may face these green projects.

A rapid, efficient, and one-pot protocol has been developed for the synthesis of cyclized 2,6-dimethyl-5-substituted-thiazolo[3,2-b]-s-triazoles (3a–c) through the interaction of 5-methyl-1H-s-triazole-3-thiol (1) with aliphatic ketones (2a–d) in refluxing acetic acid in the presence of a catalytic amount of sulfuric acid (AcOH/H+) while with aromatic ketones (5a–d), a mixture of uncyclized 3-methyl-s-triazolylthioacetophenone derivatives (6a–d) and cyclized 6-aryl-2-methyl-thiazolo[3,2-b]-s-triazoles (7a–d) has been produced. With this catalytic system, inexpensive sulfuric acid was utilized as a catalyst, which prevented the production of poisonous and irritating halo carbonyl compounds. On the other hand, the interaction of s-triazole 1 with cyano compounds (9a,b) afforded the corresponding 6-amino-2-methyl-5-substituted-thiazolo[3,2-b]-s-triazoles (10a,b). Similarly, treatment of 4-amino-3-methyl-s-triazole-5-thiol (12) with aliphatic and aromatic ketones (2c and 5a–e) afforded directly 3-methyl-7H-s-triazolo[3,4-b]-1,3,4-thiadiazines (13a and 14a–e). Further, reaction of 12 with cyano compounds (9a,b) under the same reaction conditions yielded the corresponding 3-methyl-s-triazolo[3,4-b]-1,3,4-thiadiazole derivatives (15a,b). The reaction mechanism was studied, and the structures of all novel compounds were verified using spectroscopy and elemental analysis. Moreover, the potential application of the synthesized compounds toward heavy metal ions and inorganic anion removal from aqueous solution has been investigated. The removal effectiveness for metal ions reached up to 76.29%, while for inorganic anions it reached up to 100%, indicating that such synthesized compounds are promising adsorbents for water remediation.

A field experiment was conducted to study the effect of the source and level of addition of nano-zinc oxide on the growth and yield of IPA-99 wheat cultivar grown in desert soil conditions and compare it with regular zinc fertilizers. Fertilizers were sprayed on the soil, the nano-fertilizers included three sources of zinc, nano-metallic zinc oxide (ZnnO), zinc-chelated nano-fertilizer ZnnDTPA, and nano-zinc humate (ZnnHA). The nano-fertilizers were added at levels of 1 and 2 kg ha-1. Whereas the regular zinc fertilizers, ZnO, ZnDTPA, and ZnHA, were added at a level of 4 and 8 kg ha-1 in addition to the control treatment without addition. After harvest, the grain yield, straw yield, and the concentration of zinc, nitrogen, phosphorous, and potassium in the wheat grain were estimated. The results showed that zinc nano fertilizers had a significant effect in increasing the studied plant traits compared to the control treatment, Zinc humate nano fertilizer gave the highest increase in all studied plant traits among the nano-fertilizers, as it achieved an increase in grain yield, straw yield, zinc, nitrogen, phosphorous and potassium concentrations in grains by 45.36%, 57.01%, 409.43%, 42.36%, 98.20%, and 38.56 % respectively over the control treatment. The zinc nano-fertilizers had a significant effect on increasing the yield of grains and the concentration of nitrogen and potassium in the grains compared to the regular zinc fertilizers. While the results showed there was no significant difference in straw yield and the concentration of zinc and phosphorous in the grains between nano and normal zinc fertilizer.

Propolis, a resin produced by honeybees, has long been used as a dietary supplement and folk remedy, and more recent preclinical investigations have demonstrated a large spectrum of potential therapeutic bioactivities, including antioxidant, antibacterial, anti-inflammatory, neuroprotective, immunomodulatory, anticancer, and antiviral properties. As an antiviral agent, propolis and various constituents have shown promising preclinical efficacy against adenoviruses, influenza viruses, respiratory tract viruses, herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), human immunodeficiency virus (HIV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Over 300 chemical components have been identified in propolis, including terpenes, flavonoids, and phenolic acids, with the specific constituent profile varying widely according to geographic origin and regional flora. Propolis and its constituents have demonstrated potential efficacy against SARS-CoV-2 by modulating multiple pathogenic and antiviral pathways. Molecular docking studies have demonstrated high binding affinities of propolis derivatives to multiple SARS-CoV-2 proteins, including 3C-like protease (3CLpro), papain-like protease (PLpro), RNA-dependent RNA polymerase (RdRp), the receptor-binding domain (RBD) of the spike protein (S-protein), and helicase (NSP13), as well as to the viral target angiotensin-converting enzyme 2 (ACE2). Among these compounds, retusapurpurin A has shown high affinity to 3CLpro (ΔG = −9.4 kcal/mol), RdRp (−7.5), RBD (−7.2), NSP13 (−9.4), and ACE2 (−10.4) and potent inhibition of viral entry by forming hydrogen bonds with amino acid residues within viral and human target proteins. In addition, propolis-derived baccharin demonstrated even higher binding affinity towards PLpro (−8.2 kcal/mol). Measures of drug-likeness parameters, including metabolism, distribution, absorption, excretion, and toxicity (ADMET) characteristics, also support the potential of propolis as an effective agent to combat COVID-19.

Wasps, members of the order Hymenoptera, are distributed in different parts of the world, including Brazil, Thailand, Japan, Korea, and Argentina. The lifestyles of the wasps are solitary and social. Social wasps use venom as a defensive measure to protect their colonies, whereas solitary wasps use their venom to capture prey. Chemically, wasp venom possesses a wide variety of enzymes, proteins, peptides, volatile compounds, and bioactive constituents, which include phospholipase A2, antigen 5, mastoparan, and decoralin. The bioactive constituents have anticancer, antimicrobial, and anti-inflammatory effects. However, the limited quantities of wasp venom and the scarcity of advanced strategies for the synthesis of wasp venom’s bioactive compounds remain a challenge facing the effective usage of wasp venom. Solid-phase peptide synthesis is currently used to prepare wasp venom peptides and their analogs such as mastoparan, anoplin, decoralin, polybia-CP, and polydim-I. The goal of the current review is to highlight the medicinal value of the wasp venom compounds, as well as limitations and possibilities. Wasp venom could be a potential and novel natural source to develop innovative pharmaceuticals and new agents for drug discovery.

Wasps, members of the order Hymenoptera, are distributed in different parts of the world, including Brazil, Thailand, Japan, Korea, and Argentina. The lifestyles of the wasps are solitary and social. Social wasps use venom as a defensive measure to protect their colonies, whereas solitary wasps use their venom to capture prey. Chemically, wasp venom possesses a wide variety of enzymes, proteins, peptides, volatile compounds, and bioactive constituents, which include phospholipase A2, antigen 5, mastoparan, and decoralin. The bioactive constituents have anticancer, antimicrobial, and anti-inflammatory effects. However, the limited quantities of wasp venom and the scarcity of advanced strategies for the synthesis of wasp venom’s bioactive compounds remain a challenge facing the effective usage of wasp venom. Solid-phase peptide synthesis is currently used to prepare wasp venom peptides and their analogs such as mastoparan, anoplin, decoralin, polybia-CP, and polydim-I. The goal of the current review is to highlight the medicinal value of the wasp venom compounds, as well as limitations and possibilities. Wasp venom could be a potential and novel natural source to develop innovative pharmaceuticals and new agents for drug discovery.

Thienopyrimidine derivatives are well-known in various pharmaceutical and biomedical domains. In this work, a series of efficacious and novel strategies for the synthesis of thienopyrimidines starting from 2-amino-3-carboethoxy-4,5,6,7-tetrahydrobenzo[b]thiophene has been developed. The regioselectivity of these synthetic strategies was investigated using density functional theory computation and spectroscopic analysis. In addition, the chemical structures of the new thienopyrimidines and their reaction mechanisms, as well as the biological activity of selected compounds were studied.

Wasps, members of the order Hymenoptera, are distributed in different parts of the world, including Brazil, Thailand, Japan, Korea, and Argentina. The lifestyles of the wasps are solitary and social. Social wasps use venom as a defensive measure to protect their colonies, whereas solitary wasps use their venom to capture prey. Chemically, wasp venom possesses a wide variety of enzymes, proteins, peptides, volatile compounds, and bioactive constituents, which include phospholipase A2, antigen 5, mastoparan, and decoralin. The bioactive constituents have anticancer, antimicrobial, and anti-inflammatory effects. However, the limited quantities of wasp venom and the scarcity of advanced strategies for the synthesis of wasp venom's bioactive compounds remain a challenge facing the effective usage of wasp venom. Solid-phase peptide synthesis is currently used to prepare wasp venom peptides and their analogs such as mastoparan, anoplin, decoralin, polybia-CP, and polydim-I. The goal of the current review is to highlight the medicinal value of the wasp venom compounds, as well as limitations and possibilities. Wasp venom could be a potential and novel natural source to develop innovative pharmaceuticals and new agents for drug discovery.

High-molecular-weight PLA440-b-PEO454-b-PLA440 (LEL) triblock copolymer was synthesized through simple ring-opening polymerization (ROP) by using the commercial homopolymer HO-PEO454-OH as the macro-initiator. The material acted as a single template to prepare the large mesoporous carbons by using resol-type phenolic resin as a carbon source. Self-assembled structures of phenolic/LEL blends mediated by hydrogen bonding interaction were determined by FTIR and SAXS analyses. Through thermal curing and carbonization procedures, large mesoporous carbons (>50 nm) with a cylindrical structure and high surface area (>600 m2/g) were obtained because the OH units of phenolics prefer to interact with PEO block rather than PLA block, as determined by FTIR spectroscopy. Furthermore, higher CO2 capture and good energy storage performance were observed for this large mesoporous carbon, confirming that the proposed approach provides an easy method for the preparation of large mesoporous materials.

An efficient, simple, and one-pot double Mannich reaction was performed for the synthesis of cyclized 2-methyl-6-substituted-6,7-dihydro-5

New porphyrin-functionalized benzoxazine (Por-BZ) in high purity and yield was synthesized in this study based on 1H and 13C NMR and FTIR spectroscopic analyses through the reduction of Schiff base formed from tetrakis(4-aminophenyl)porphyrin (TAPP) and salicylaldehyde and the subsequent reaction with CH2O. Thermal properties of the product formed through ring-opening polymerization (ROP) of Por-BZ were measured using DSC, TGA and FTIR spectroscopy. Because of the rigid structure of the porphyrin moiety appended to the benzoxazine unit, the temperature required for ROP (314 °C) was higher than the typical Pa-type benzoxazine monomer (ca. 260 °C); furthermore, poly(Por-BZ) possessed a high thermal decomposition temperature (Td10 = 478 °C) and char yield (66 wt%) after thermal polymerization at 240 °C. An investigation of the thermal and luminescence properties of metal–porphyrin complexes revealed that the insertion of Ni and Zn ions decreased the thermal ROP temperatures of the Por-BZ/Ni and Por-BZ/Zn complexes significantly, to 241 and 231 °C, respectively. The metal ions acted as the effective promoter and catalyst for the thermal polymerization of the Por-BZ monomer, and also improved the thermal stabilities after thermal polymerization.

In this study we synthesized a triazine-formaldehyde phenolic resin as a nitrogen-containing resol (N-resol) through the condensation of 2,4,6-tris(4-hydroxyphenyl)triazine and formaldehyde. We then used this N-resol as a carbon and nitrogen atom source, mixing it with a diblock copolymer of PEO-b-PCL as the soft template, for the direct synthesis of N-doped mesoporous carbons. Interestingly, the self-assembled N-resol/PEO-b-PCL blends underwent a mesophase transition from cylinder to gyroid and back again to cylinder structures upon increasing the N-resol concentration (i.e., cylinder at 50/50; gyroid at 60/40; cylinder at 70/30). After removing the soft template at 700 °C, the resultant N-doped mesoporous carbons possessed high N atom contents (up to 13 wt%) and displayed gyroid and cylinder nanostructures. The synthesized N-doped mesoporous carbons exhibited excellent CO

Studies related to BIM implementation status, awareness level, and implementation challenges and barriers in selected GCC have been well reported. Despite the vast Saudi Arabian economy and the volume of construction projects being undertaken in the Kingdom, there is no clear evidence for any such study conducted within the local construction industry. Thus, the authors make a pioneering attempt to first examine the level of subcontractors’ awareness and preparedness for BIM implementation in construction projects in the Saudi Arabian construction industry. This is necessary because the subcontracting sector, which comprises mainly of the small- and medium-scale construction companies greatly outnumber the big construction companies in the local construction industry. Thus, industry wide survey was conducted to this effect. Findings of the study reveal a widespread lack of BIM knowledge across subcontracting sector of Saudi Arabian construction industry. Most of the subcontractors lack some basic understanding of the functions of BIM in the feasibility, construction and maintenance management stages of construction project. Other findings suggest reluctance among the subcontracting companies toward implementing BIM in construction projects. Thus, to maximize full advantages of BIM and to facilitate full adoption of BIM among the subcontracting sector, valuable recommendations were highlighted. It is anticipated that the findings of this paper could be valuable to regulators of the Saudi Arabian Construction Industry and serve as basis for urgent preparation of guidelines and policies to improve the general level of BIM adoption and expertise within the industry.

A rapid and efficient one-pot protocol has been developed for the synthesis of s-triazolo[3,4-b][1,3,4]thiadiazine and s-triazolo[3,4-b][1,3,4]thiadiazole nanoarchitectonics through the reaction of s-triazoles with ketones and nitriles in acetic acid containing a catalytic amount of sulfuric acid under microwave irradiation in excellent yields. With this catalytic reaction, the cheap sulfuric acid as well as other acids were examined as catalysts and the highly toxic and irritating haloketones and halonitriles were avoided to form. The effects of microwave power, temperature, time, solvent and catalyst were examined. This method achieved a better performance; e.g., higher yields, shorter reaction time and easier work-up as compared to other conventional methods. Therefore, the proposed method will be readily applicable to the synthesis of biologically important compounds containing s-triazolo[3,4-b][1,3,4]thiadiazine and s-triazolo[3,4-b][1,3,4]thiadiazole framework.

Nature has provided many drugs capable of treating and alleviating human diseases. Terrestrial plants, bacteria, insects, fungi, and bee products have played major roles in traditional medicine. Secondary metabolites from a range of bee products, such as honey, pollen, propolis, royal jelly, and bee venom, represent a huge repository of chemical biodiversity, providing renewable and rewarding sources of therapeutic substances, either directly from nature or as synthesized analogues. Bee venom in particular has attracted a lot of attention due to its wide range of bioactive components, such as melittin, apamin, adolapin, secapin, tertiapin, mast cell-degranulating phospholipase A2, and hyaluronidase. Histamine, epinephrine, and macromolecules (such as lipids, carbohydrates, and free amino acids) are further components. Rapid developments in chromatographic and spectroscopic techniques have enabled the identification of novel compounds as potential pharmaceutical constituents, including acid phoshatase, dipeptidyl peptidase, Api m 6, CUB serine protease, melittin-S, and secapin-1,2. This chapter updates knowledge on the BV chemical profile, in particular what was learned between 2007 and 2016. This includes such aspects as traditional uses, venom collection, factors affecting bee venom content, isolated components, and finally the synthesis of some recently isolated compounds.

Aims: The escalating demands for traditional fossil fuels with unsecured deliverance and issues of climate change compel the researchers to develop alternative fuels like bioethanol. This study examines the prospect of biofuel production from high carbohydrate containing lignocellulosic material, e.g. sugarcane bagasse through biological means. Methodology and Results: Cellulolytic enzymes were collected from the culture filtrate of thermotolerant Trichodermaviride grown on variously pre-treated sugarcane bagasse. CMCase and FPase enzyme activities were determined as a measure of suitable substrate pre-treatment and optimum condition for cellulolytic enzyme production. The highest CMCase and FPase activity was found to be 1.217 U/ml and 0.109 U/ml respectively under the production conditions of 200 rpm, pH 4.0 and 50 °C using steamed NaOH treated bagasse as substrate. SEM was carried out to compare and confirm the activity of cellulolytic enzymes on sugarcane bagasse. Saccharification of pre-treated bagasse was carried out with crude enzymes together using a two-factor experimental design. Under optimized conditions the pre-treated bagasse was saccharified up to 42.7 % in 24 h. The hydrolysate was concentrated by heating to suitable concentration and then used for fermentation by an indigenous isolate of Saccharomyces cerevisiae. With 50 and 80 % brix containing liquor the concentration of alcohol was 0.579 % and 1.15 % respectively. Conclusion, significance and impact of study: This is the first report in Bangladesh for the production of cellulosicethanol using local isolates. Though the rate of alcohol production was very low, a great impetus in this field can maximize the production thereby meet the demand for fuel in future.

The key to a successful implementation of a build-operate-transfer (BOT) infrastructure project is in-depth analysis of all aspects related to economic, environmental, social, political, legal, and financial feasibility of the project. For these reasons, the analysis of the project feasibility decision needs a technique to include the qualitative decision factors that have a strong impact on the project. This paper aims to introduce a decomposed evaluation model developed to assess the most common significant decision factors that strongly affect the feasibility of BOT projects. The paper describes the viability decision factors that were identified and screened with the assistance of a group of industry experts. This analysis yielded 21 significant factors that would have a certain impact on the feasibility of any BOT project. These factors were classified into three relative categories forming the structure of the suggested project viability model. This model presents a new approach, based on the analytical hierarchy process technique, to evaluate the relationships between decision factors related to project feasibility determination. The new approach has been validated by information obtained from three case studies of BOT projects. The proposed approach to project feasibility evaluation aims to increase the decision maker's ability to determine the factors contributing the most to the viability to the BOT project at hand.

Correction for ‘An efficient and rapid intramolecular cyclization of a quadruple Mannich reaction for one-pot synthesis of pentaazaphenalenes and their antimicrobial activities’ by Ahmed F. M. EL-Mahdy et al., RSC Adv., 2016, 6, 92134–92143.

Recently, design change comes to the fore as main cause of delay in construction projects in the Kingdom of Saudi Arabia (KSA). In this study, in-depth analysis of design change as a cause of delay was investigated in both design and procurement and construction phases of the project. Twenty-five design change factors were collected from literature and classified under two categories (during procurement phase and during construction phases). Structured survey was sent to construction project parties (clients, designers and consultants, and contractors) who are involved in the construction industry in KSA and Gulf area. Based on valid responses, these factors were analysed and weighed by using AHP technique. Errors in original design, unforeseen site conditions, change in client's design requirement, and poor communication between project parties gained the highest weights as main causes of design change. Some recommendations were provided to minimise the impact of these factors on project construction.

Successful implementation of build-operate-transfer (BOT), infrastructure projects is dependent on a full and thorough analysis of factors that include social, economic and political, amongst others. Alongside the financially focused evaluations, qualitative factors will also have a strong impact on the project and so require specific techniques for the analysis. This paper presents a new evaluation framework, based on the analytical hierarchy process technique, for use in assessing the most common and significant decision factors relating to risks in BOT projects. Consultations with an expert group identified a series of risk decision factors. The results produced twenty-eight critical Risk Factors, which have a particular impact on the risks of BOT projects. The project risk framework was constructed by classifying the factors into five categories. The framework was successfully validated using a BOT project case study. This research seeks to make a valuable contribution to the field by having developed and validated a new risk evaluation framework, focused on BOT projects in Kuwait.

The determination of aerodynamic coefficients by shell designers is a critical step in the development of any projectile design. Of particular interest is the determination of the aerodynamic coefficients at transonic speeds. It is in this speed regime that the critical aerodynamic behavior occurs and a rapid change in the aerodynamic coefficients is observed. Two-dimensional, transonic, flow field computations over projectiles have been made using Euler equations which were used for solution with no special treatment required. In this work a solution algorithm is based on finite difference MacCormack’s technique for solving mixed subsonic-supersonic flow problem. Details of the asymmetrically located shock waves on the projectiles have been determined. Computed surface pressures have been compared with experimental data and are found to be in good agreement. The pitching moment coefficient, determined from the computed flow fields, shows the critical aerodynamic behavior observed in free flights.