Browsing by Author "Prof. Dr. Zulfiqar Ali"

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Application of Hyphenated Analytical Techniques and Chemometrics in Drugs Facilitated Crime: A Forensic Investigation
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Uswa Adil; FA22-R06-006; Prof. Dr. Zulfiqar Ali; LHR TP 9312
Drug-facilitated crimes are those in which a person is made a victim of a criminal conduct by means of the incapacitating impact of alcohol or illicit drugs. In drugs facilitated crimes (DFCs), advanced analytical techniques are increasingly used for drug identification. They serve as vital investigative tools for handling intricate analytical problems. In a simulated crime scene, the project's goal was to identify and examine CNS depressants (Alprazolam, Diazepam, Tramadol, Buspirone, and Clonazepam) using sophisticated hyphenated analytical techniques and chemometric methods. The principal objective of this research was to use dried spots on cotton, surfaces spiked with different CNS depressants, and beverages like Pepsi, apple juice, and milk to develop realistic crime scene scenes. Techniques including attenuated total reflectance-Fourier-transform infrared spectroscopy (ATR-FTIR), high-performance liquid chromatography-diode array detector (HPLC-DAD), and gas chromatography mass spectrometry (GC-MS) were used to precisely identify and discriminate these drugs. By combining ATR-FTIR with chemometric methods like principal component analysis (PCA) and discriminant analysis (PCA-DA), the precise classification of unknown depressants was accomplished. GC-MS and HPLC-DAD procedures were developed to validate the findings. When CNS depressants were extracted from suspected CNS depressants spots in crime scene samples, acceptable recoveries of 75% to 92% were obtained. As a result, this holistic approach offered reliable and effective techniques for conducting forensic investigations.
Developing High Strength Adhesives for Metal- Polymer Bonding in Industrial and Strategic Applications
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Fakhra Mansha; CIIT/SP24-R06-018/LHR; Prof. Dr. Zulfiqar Ali; LHR TP 10023
An adhesive is a non-metallic compound that has a wide range of applications as compared to traditional methods. Silicones, acrylics, polyurethanes and epoxy are some major structural adhesives that are widely used in structural applications. Metal rubber bonding is important in many industrial sectors to achieve hybrid strength, durability and for damping. It provides elasticity and resistance to temperature and chemicals. But due to surface energy mismatch, manufacturing and inappropriate adhesive selection M-R bonding face challenges in high strength. To overcome this challenge epoxy is selected as an adhesive that has high strength, durability, high chemical and thermal resistance and having tunable properties via curing agents, fillers, coupling agents and modifiers. However, brittleness and restricted pot life limits its applications. So, by adding appropriate fillers, proper surface treatment, adding modifiers and coupling agents adhesion strength and toughness of epoxy enhanced. By incorporating filler content 3%, 5% and 7% with APTES and PEG diff content in epoxy resin and hardener adhesive is formulated. Mechanical and chemical surface treatment applied to steel metal plates, rubber and adhesive layer applied on steel plates and then placed in compression molding for bonding. By performing various characterization techniques Lap shear test, FTIR, XRD and SEM epoxy adhesive is characterized and from these techniques it observed that 5% filler content is optimal value and it gives 53MPa adhesion strength that is 85% highest then neat epoxy adhesive.
Development of Rubber/Metal Adhesive for Industrial Application
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2024) Amina Noor; FA22-R06-004; Prof. Dr. Zulfiqar Ali; LHR TP 9322
Adhesives have a lot of applications in everyday life from aeronautics to aerospace industries due to its excellent properties. Adhesives are available into different forms liquid or semi liquid form with some other forms like glues, gums, cements, and bonding agent. Adhesives provide more good stress distribution and flexibility in comparison of riveting and welding. Adhesives are classified into major types i.e. Structural and Non-Structural adhesives. Structural Adhesives are epoxides, acrylics, and polyurethane. Non-Structural adhesives are Pressure sensitive adhesives and bio adhesives. Structural adhesives are preferable over non-structural adhesives because structural adhesives become integral part of material and have more strength. Epoxies are thermosetting materials. They are mostly used due to its good mechanical properties, corrosion, temperature, and environment resistant. Bisphenol A di glycidyl ether in epoxies is mostly popular among epoxies. Epoxy adhesive has been prepared and characterized for rubber metal binding applications. Boric acid, Bisphenol A di glycidyl ether and 3-trimethoyxsilylpropyl chloride was added into a beaker and stir for 15 minutes at 80C.Then, PVA was added into stirred material and heated for two hours at 80C.Epoxy adhesives was synthesized for application rubber metal binding. To increase the strength, metal surface was treated by etching with sulfuric acid or hydrochloric acid. NBR was soften with aid of toluene to increase the adhesion. Rubber was bonded to metal with help of epoxy adhesives. Epoxy adhesives was characterized by FTIR, TGA, DSC and SEM.The rubber metal bonded part was characterized by shear strength. FTIR has showed siloxane and borate ester bond according literature review. The GPC has showed mass distribution because the presence of vinyl capping agent. The shear strength has showed strength has increased up to 1.7 MPa. Development of sustainable and eco-friendly adhesives are future goals.
Eco Friendly Filler Modified Sustainable Polymer Composites for Improved Mechanical Performance
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) RASHID KHAN; CIIT/SP24-R06-025/LHR; Prof. Dr. Zulfiqar Ali; LHR TP 10028
This work presents a systematic investigation of kraft lignin as a sustainable bio-filler for elastomeric composites, focussing on chemical modification (nickel coordination), comprehensive physico-chemical characterisation, formulation into nitrile butadiene rubber (NBR) compounds, and comparison with conventional inorganic fillers. Motivated by the environmental and resource supply problems of petrochemical fillers, the study situates lignin within the circular bioeconomy paradigm and reviews current approaches to compatibility enhancement and performance optimisation of bio-fillers. The work details a reproducible protocol to synthesise nickel-coordinated lignin nanoparticles, and applies FTIR, UV–Vis and Raman spectroscopy to verify metal chelation and preservation of lignin’s aromatic backbone. Dispersion, thermal stability and interfacial behaviour are quantitatively and qualitatively evaluated; modified lignin demonstrates reduced hydroxyl accessibility, characteristic spectral shifts consistent with Ni²⁺ coordination, and absorption features indicative of discrete chelate complexes rather than metallic aggregates. When incorporated into NBR matrices under controlled mixing and cure conditions, chemically modified lignin particularly following hydrophobization/compatibilisation strategies yields composite property profiles (hardness, abrasion resistance, and modulus) comparable to, and in specific metrics competitive with, carbon black and silica filled analogues. The manuscript identifies key process windows for filler loading and highlights residual challenges (agglomeration, polarity mismatch, thermal-processing limits) that determine the practical ceiling for lignin substitution in high-performance elastomers
Synthesis and Characterization of Conducting Filler-Based Elastomer Composites for Electromagnetic Shielding Applications
(Library Information Services COMSATS University Islamabad Lahore Campus, 2023-02-27) Rida Fatima; SP22-R06-013; Prof. Dr. Zulfiqar Ali; LHR TP 8652
The evolution of advanced communications systems and other electro-electronic gadgets has led to a type of electromagnetic pollution that has an impact on both the functionality of other equipment and people's health. There is a growing need for effective shielding materials to control EMI and related issues. A variety of composite materials have been developed using various combinations of dissimilar elements because it is widely known that single configuration cannot achieve necessary materials EMI-shielding (EMI-S) efficacy. The most popular materials having EMI shielding materials are made of metals with having inherent flaws including being heavy, more prone to corrosion, expensive, complex to produce, etc. Shields with to overcome these constraints, metal-based structure was modified using a variety of structural types and other materials. Conducting polymer-based composites have distinguished themselves from other classes of materials that form composite produced as Shielding-EMI components due to unique characteristics such as lower weight, environmental stability, long-life, durability, and minimal corrosive tenability. Here, in this work, Conducting Filler-Based Elastomer Composites synthesized and characterized by melt mixing method for electromagnetic shielding applications. The surface modification confirmed by different characterization techniques i.e., Fourier-transform infrared spectroscopy (FTIR), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). For the mechanical and EMI Shielding applications composites material characterized by Universal testing machines (UTMs) that test mechanical properties such as tensile, flexural, compressive and shear. Thermogravimetric analysis (TGA) analysis for the measurement of thermal stability of material electrical conductance measurement and use of Vector Network Analyzer by Rhode and Shwarz for EMI Shielding.