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21.
Sana Sadaf Haq Nawaz Bhatti Muhammad Arif Misbah Amin Farva Nazar 《Chemistry and Ecology》2013,29(3):252-264
This paper reports the application of Box-Behnken experimental design to illustrate the adsorption of direct dyes (Indosol Black NF and Indosol Orange RSN) using polyethyleneimine (PEI)-treated peanut husk biomass. The effect of three independent variables (initial dyes concentration, biosorbent dose and pH) was investigated during the study. Maximum biosorption capacity (141 and 98.2 mg/g) of PEI-pretreated biomass was achieved with 200 mg/L initial dye concentration and 0.05 g/50 mL biomass dose for Indosol Black NF and Indosol Orange RSN, respectively. Acidic pH was found to be favourable for maximum dyes removal. Characterisation of biosorbent was carried out through Fourier transform-infrared spectroscopy (FT-IR), scanning electron microscopy, thermogravimetric analysis (TGA) and point of zero charge determination. FT-IR analyses confirmed the involvement of carboxylic and carbonyl groups. The desorption study was also conducted to check out the possibility of regeneration of dyes and adsorbent and it was found that 51.58 and 76.6% of Indosol Black NF and Indosol Orange RSN, respectively, can be desorbed from the loaded biosorbent by using 1 M NaOH solution. The results indicated that PEI-treated peanut husk biomass can be used as an efficient biosorbent for the removal of Indosol Black NF and Indosol Orange RSN dyes from aqueous solutions. 相似文献
22.
Nawaz Haq Shah Mohibbullah Nishan Umar Iqbal Jibran Mannan Rabia 《Journal of Polymers and the Environment》2021,29(11):3548-3560
Journal of Polymers and the Environment - The alkali-soluble cell wall polysaccharides (CWPs), extracted from Nelumbo nucifera rhizome flour (NNRF), were treated with microwave radiation to modify... 相似文献
23.
The present work describes the removal of Novacron Golden Yellow (NGY) dye from aqueous solutions using peanut hulls. The experiments were performed with native, pretreated and immobilised forms of peanut hulls. The effect of various operational parameters (pH, biosorbent dose, initial dye concentration and temperature etc.) was explored during batch study. NGY showed maximum removal at low pH and low biosorbent dose. High initial dye concentration facilitated the biosorption process. Maximum dye removal with native, pretreated and immobilised biomass was found to be 35.7, 36.4 and 15.02 mg/g respectively. The experimental data were subjected to different kinetic and equilibrium models. The kinetic data confirmed the fitness of pseudo-second-order rate law for NGY biosorption. The equilibrium modelling was carried out by Freundlich, Langmuir and Temkin models. The isothermal data of NGY removal were best described by Freundlich adsorption isotherm. Negative values of Free energy change (Δ G0) for NGY with native and pretreated biomass depicted the spontaneous nature of biosorption process. In column mode, the effects of bed height, flow rate and initial dye concentrations were optimised. Maximum NGY biosorption (7.28 mg/g) was observed with high bed height, low flow rate and high initial concentration in continuous mode. Bohart–Adams model best fitted to the data obtained from column studies. The results indicated that the peanut hulls could be used effectively for the removal of dyes containing wastewater. 相似文献
24.
The alkaline conditions for extraction of natural dye from Henna leaves were optimized and the resulting extract was used to further optimize its dyeing conditions on cotton by exhaust method. Dyeings without any mordant were compared with those obtained with premordanting and postmordanting with alum and iron. It was found that dyeings produced with alkaline extracts of Henna leaves have better colour strength than the dye extracts obtained in distilled water. Furthermore, dyeings with alkaline extracts have moderate to good fastness properties and that mordanting did not result in any significant improvement in fastness properties. Finally, in comparative studies between synthetic and this natural dye, it was inferred that natural dye has good potential to act as co-partner with synthetic dye. 相似文献
25.
Anwar Awais Ahmad Nawaz Madni Ghulam Rasool 《Environmental science and pollution research international》2020,27(7):7053-7070
Environmental Science and Pollution Research - Belt and Road initiative has been proposed by China to initiate the cooperation among relevant countries in sector of energy and Trade. The... 相似文献
26.
Ashraf Sohaib Ashraf Shoaib Ashraf Moneeb Imran Muhammad Ahmad Choudhary Zawar Ahmad Hafsa Hadiqa Tul Awais Abeer Bin Kalsoom Larab Farooq Iqra Habib Zaighum Ashraf Sidra Iqbal Qurrat Ul Ain Ghufran Muhammad Sherazi Syed Sami Hussain Akram Muhammad Kiwan Akmal Rutaba Rafique Sundas Nawaz Khawar Safdar Zartasha Siddique Uzma Nasim Hassan Muhammad Arshad Shahroze Virk Abdul Rehman Ashraf Muhammad Saboor Qazi Abdul Humayun Ayesha Izhar Mateen 《Environmental science and pollution research international》2022,29(6):8382-8392
27.
M. Waseem Mumtaz Ahmad Adnan Hamid Mukhtar Khalid Nawaz Ahtisham Raza Zahoor Ahmad 《Environmental monitoring and assessment》2011,172(1-4):581-587
The present work deals with the assessment of bacteriological contamination along with some physico-chemical parameters of water samples from Lahore canal. ANOVA showed that the observed p values of log-transformed viable plate counts, total suspended solids, turbidity, and biological oxygen demand are 0.000, 0.000, 0.000, and 0.000, respectively, which are <0.05, while the p value of total coliforms, total fecal coliforms, and Escherichia coli are 0.728, 0.827, and 0.081, respectively which are >0.05. Significant correlation was observed between log-transformed viable plate counts (CFU), biological oxygen demand, total suspended solids, and turbidity. Further regression analysis revealed that simple line regression model is fit for log-transformed viable plate counts and total suspended solids, log-transformed viable plate counts and turbidity, turbidity and total suspended solids, biological oxygen demand and total suspended solids, biological oxygen demand and log-transformed viable plate counts, and biological oxygen demand and turbidity. 相似文献
28.
An Hui Razzaq Asif Nawaz Ahsan Noman Sohail M. Khan Syed Abdul Rehman 《Environmental science and pollution research international》2021,28(37):51022-51045
Environmental Science and Pollution Research - The Belt and Road initiative (BRI) mainly relies on the traditional and underdeveloped logistical trade routes including the terrestrial and oceanic... 相似文献
29.
Many silver(Ag)containing consumer-products(e.g.textiles)release Ag into the environment,posing ecotoxicological risks.Ag recovery mitigates environmental hazards,recycles Ag,and leads to sustainability.In the present work,Ag has been recovered as Ag~0nanoparticles from the spent solution(thiourea(TU)~0.5 mol/L pH~1.1–1.2,and Ag~550 mg/L)obtained from the regeneration of an Ag-loaded resin using a simple undivided electrolytic cell.The reclaimed regenerant solution has been recycled and reused in a closed-loop scheme over multiple cycles.The process parameters,i.e.,current(0.05 A)and stirring speed(600 r/min),have been optimized for Ag recovery of~94%and TU loss of~2%.The reclaimed regenerant solution has been shown to regenerate Ag-loaded resin samples with90%regeneration efficiency over 4 cycles of consecutive extraction and regeneration.The recovered Ag~0nanoparticles are monodisperse,consistently spherical in shape,and have a mean diameter of~6 nm with standard deviation of the Gaussian fit as~2.66 nm. 相似文献
30.
Ishfaq Ahmed Muhammad Zeeshan Shaukat Ahmad Usman Muhammad Musarrat Nawaz Mian Sajid Nazir 《International journal of occupational safety and ergonomics》2018,24(2):240-250
This research covers the current status of occupational health and safety (OHS)-related practices in the informal construction segment of Pakistan. Data were collected, through interviews, from 316 construction sites employing 3577 workers. The results of the study reveal that both employers and workers lack knowledge of OHS laws/standards and no practices of this nature are enacted at these construction sites. Alarmingly, work-related accidents, whenever they happen, are not given due attention and there is no formal injury-report system. The informal construction industry employs a huge portion of the informal workforce, and lack of OHS happens at tremendous human cost. These research findings may thus play their role in strengthening the case for reforms in the sector. This study, if properly utilized, may also enable employers of the sector by increasing their knowledge about OHS practices and, as a result, trying to offer safer environments for their workers. 相似文献