A review of novel green adsorbents as a sustainable alternative for the remediation of chromium (VI) from water environments.

The presence of heavy metal, chromium (VI), in water environments leads to various diseases in humans, such as cancer, lung tumors, and allergies. This review comparatively examines the use of several adsorbents, such as biosorbents, activated carbon, nanocomposites, and polyaniline (PANI), in terms of the operational parameters (initial chromium (VI) concentration (Co), temperature (T), pH, contact time (t), and adsorbent dosage) to achieve the Langmuir's maximum adsorption capacity (qm) for chromium (VI) adsorption. The study finds that the use of biosorbents (fruit bio-composite, fungus, leave, and oak bark char), activated carbons (HCl-treated dry fruit waste, polyethyleneimine (PEI) and potassium hydroxide (KOH) PEI-KOH alkali-treated rice waste-derived biochar, and KOH/hydrochloric acid (HCl) acid/base-treated commercial), iron-based nanocomposites, magnetic manganese-multiwalled carbon nanotubes nanocomposites, copper-based nanocomposites, graphene oxide functionalized amino acid, and PANI functionalized transition metal are effective in achieving high Langmuir's maximum adsorption capacity (qm) for chromium (VI) adsorption, and that operational parameters such as initial concentration, temperature, pH, contact time, and adsorbent dosage significantly affect the Langmuir's maximum adsorption capacity (qm). Magnetic graphene oxide functionalized amino acid showed the highest experimental and pseudo-second-order kinetic model equilibrium adsorption capacities. The iron oxide functionalized calcium carbonate (IO@CaCO3) nanocomposites showed the highest heterogeneous adsorption capacity. Additionally, Syzygium cumini bark biosorbent is highly effective in treating tannery industrial wastewater with high levels of chromium (VI).

Wind speed pattern data and wind energy potential in Pakistan: current status, challenging platforms and innovative prospects.

Energy is an essential parameter for the economic growth and sustainable development of any country. Due to the rapid increase in energy demand, depletion of fossil fuels and environmental concerns, many developing and developed countries are moving towards alternative renewable resources such as solar energy, wind energy and biomass. Wind energy as a renewable energy source is gaining a lot of significant attention. Wind energy is a sustainable solution to produce energy having potential benefits such as clean source, reduced toxic gases emission and environmental friendly protocol for operation. Pakistan is among the top countries facing the worst energy crisis due to different political and financial issues. Pakistan is blessed with a huge potential of wind energy having all the basic requirements such as windy regions and good wind speed for harnessing energy. Pakistan can utilize the potential of wind energy to reduce the problem of energy outrage in the country and also take steps towards green economy from conventional fuel economy. This critical review highlights the current status, potential and the steps taken in the past and present to overcome the energy shortage in Pakistan by employing wind energy. Outlook on wind speed data, deployment of wind energy, environmental effect of wind energy and its barriers in the adoption are discussed with recommendations and suggestions to utilize this clean energy in an effective way. Graphical abstract.

Promoting sustainability of use of biomass as energy resource: Pakistan's perspective.

Biomass is primary source of energy for household in rural communities. Developing countries are focusing on increasing utilization of indigenous energy resources for energy security and to achieve sustainable development goal. Combustion of solid biomass is the primary approach for utilizing biomass to generate electricity and heat. Sixty-eight percent of population of Pakistan is living in rural areas while 30% population is still without electricity. The traditional household appliances used for cooking and heating are less efficient, more hazardous to users, and more damaging to the environment. Low carbon energy system prerequisites access to modern energy services. This paper presents an assessment of biomass resources potential in Pakistan as renewable energy resources and reviews potentials to adopt efficient use of biomass for cooking, heating, and small decentralized electricity generation. Objective of this study is to increase the sustainability of the use of biomass as source of energy in developing countries like Pakistan by an integrating energy-efficient and modern appliances and technologies that fit into a sustainable development path. Promotion of cleaner technologies and efficient use of biomass energy constitute appropriate strategies to mitigate global climate, health risks, and help in attending the targets set by sustainable development goal (SDG) to confirm worldwide access to reliable, affordable, and modern energy services by 2030.

Use of a pedicled flap for reconstruction of extensive soft tissue defects around elbow.

OBJECTIVE: To determine the reliability of pedicled latissimus dorsi flap for reconstruction of extensive defects around the elbow in terms of flap survival and coverage of exposed bones, vessels or nerves. STUDY DESIGN: Case series. PLACE AND DURATION OF STUDY: Department of Plastic and Reconstructive Surgery at Shaikh Zayed Hospital, from February 2003 to January 2008. METHODOLOGY: Patients with extensive traumatic wounds around the elbow and wounds secondary to release of postburn elbow contracture were included. Patients above 60 years of age with previous history of myocardial infarct, heart failure, chronic obstructive pulmonary disease or insulin dependent diabetes were excluded. Pedicled latissimus dorsi flap was used for defect reconstruction. Overall flap survival and postoperative complications were the outcome measures. RESULTS: There were 28 patients, including 20 males and 8 females, age ranging from 17 to 60 years. Evaluation of the defect considering extent of tissue loss, depth of the defect and exposed vital structure was done. Myocutaneous flap was used in 4 (14%) patients. Muscle only flap was used in 24 patients (86%). Twenty five (90%) flaps survived completely and 3 (10%) had partial loss. Other minor complications were partial graft loss seen in 3 (10%) patients and wound infection seen in 2 (7%) patient. There was no considerable morbidity at donor site and all patients had satisfactory healing. CONCLUSION: Pedicled latissimus dorsi flap is a reliable and safe option for resurfacing extensive soft tissue defects of arm, elbow and forearm.