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The relationship between China and Pakistan has a long history, and the two countries have maintained a long-term cooperative partnership. Under this relationship, fruitful cultural exchanges have taken place, although occasional cultural conflicts have occurred. Based on the foundation of long-term cooperation, conflicts in cultural exchanges have been effectively resolved through mutual visits, promoting deeper understanding and trust between the two sides. Therefore, it can be said that cultural exchange between China and Pakistan is an important tool for adjusting cultural conflicts, promoting diplomatic relations, and bridging the gap between the two countries. This article reviews and examines the history of cultural exchanges between China and Pakistan and proposes a conflict adjustment framework based on "respect-understanding-communication-trust." Specific measures are also proposed, such as "establishing smooth cultural communication channels, improving conflict resolution mechanisms, deepening cultural exchange projects, and strengthening joint research projects" to adjust cultural conflicts and promote deeper cultural exchanges between the two countries.

Graphene is a unique nanocarbon nanostructure, which has been frequently used to form nanocomposites. Green-synthesized graphene has been focused due to environmentally friendly requirements in recent technological sectors. A very important application of green-synthesized graphene-based nanocomposite has been observed in energy storage devices. This state-of-the-art review highlights design, features, and advanced functions of polymer/green-synthesized graphene nanocomposites and their utility in supercapacitor components. Green graphene-derived nanocomposites brought about numerous revolutions in high-performance supercapacitors. The structural diversity of conjugated polymer and green graphene-based nanocomposites has facilitated the charge transportation/storage capacity, specific capacitance, capacitance retention, cyclability, and durability of supercapacitor electrodes. Moreover, the green method, graphene functionality, dispersion, and matrix–nanofiller interactions have affected supercapacitance properties and performance. Future research on innovative polymer and green graphene-derived nanocomposites may overcome design/performance-related challenging factors for technical usages.

Semiconductor Silicon quantum dots (SiQDs) and magnetic nanomaterials have been studied extensively for their variety of applications. We have presented a new method for the preparation of Magnetic Silicon Quantum Dots (Fe3O4/SiQDs) heterostructure nanocomposites. These nanocomposites are fluorescent, have excellent magnetic properties as well as high photocatalytic activity. Magnetic nanoparticles-semiconductor nanocomposites served as an effective recoverable photocatalyst for melamine degradation. In addition, due to their easy magnetic separation, these nanocomposites showed optimum catalytic activity for 15 cycles of usage.

Fuel cell efficiency can be improved by using progressive electrodes and electrolytes. Green nanomaterials and green technologies have been explored for the manufacturing of high-performance electrode and electrolyte materials for fuel cells. Platinum-based electrodes have been replaced with green materials and nanocomposites using green fabrication approaches to attain environmentally friendly fuel cells. In this regard, ecological and sustainable electrode- and electrolyte-based membrane electrode assemblies have also been designed. Moreover, green nanocomposites have been applied to form the fuel cell electrolyte membranes. Among fuel cells, microbial fuel cells have gained research attention for the incorporation of green and sustainable materials. Hence, this review essentially focuses on the potential of green nanocomposites as fuel cell electrode and electrolyte materials and application of green synthesis techniques to attain these materials. The design of and interactions with nanocomposites have led to synergistic effects on the morphology, impedance, resistance, power density, current density, electrochemical features, proton conductivity, and overall efficiency. Moreover, we deliberate the future significance and challenges of the application of green nanocomposites in electrodes and electrolytes to attain efficient fuel cells.

One important application of polymer/graphene nanocomposites is in membrane technology. In this context, promising polymer/graphene nanocomposites have been developed and applied in the production of high-performance membranes. This review basically highlights the designs, properties, and use of polymer/graphene nanocomposite membranes in the field of gas separation and purification. Various polymer matrices (polysulfone, poly(dimethylsiloxane), poly(methyl methacrylate), polyimide, etc.), have been reinforced with graphene to develop nanocomposite membranes. Various facile strategies, such as solution casting, phase separation, infiltration, self-assembly, etc., have been employed in the design of gas separation polymer/graphene nanocomposite membranes. The inclusion of graphene in polymeric membranes affects their morphology, physical properties, gas permeability, selectivity, and separation processes. Furthermore, the final membrane properties are affected by the nanofiller content, modification, dispersion, and processing conditions. Moreover, the development of polymer/graphene nanofibrous membranes has introduced novelty in the field of gas separation membranes. These high-performance membranes have the potential to overcome challenges arising from gas separation conditions. Hence, this overview provides up-to-date coverage of advances in polymer/graphene nanocomposite membranes, especially for gas separation applications. The separation processes of polymer/graphene nanocomposite membranes (in parting gases) are dependent upon variations in the structural design and processing techniques used. Current challenges and future opportunities related to polymer/graphene nanocomposite membranes are also discussed.

In the present work, we propose the synthesis of novel nicotinamide subsituted phthlocyanine photosensitizer (PS) and characterized by FTIR, UV–visible, H-NMR and MALDI Toff spectroscopy. Nicotinamide plays a vital rule in the central nervous system and its potential as a therapeutic for neurodegenerative disease. Nicotinamide substituted PS (3) efficiently produced ROS via type-1 process as measured by DCF assay. We observed that our PS after red light illumination (22 J/cm2) killed gram positive S. aureus upto 3 log reduction. Furher the addition of Potassium Iodide (100 mM) significantly potentiated PS at lower concentrations and enhanced the bacterial killing upto 6 log reduction against the S. aureus. We further found that the synergistic effect of PS and KI also eradicated the gram negative E. coli strain at lower concentraion of PS and found to killed E. coli upto 5 log reduction under the red light illumination at 22 J/cm2 of light dose. The conjugation of such biologically important form of vitamin B3 with PS would be a great addition and could pav the way for the novel photodynamic agent in the treatement of cancer and infectious diseases. A new symmetrical Nicotinamide tetrasubstituted zinc phthalocyanine (3) was synthesized. Upon addition of potassium Iodide with PS, the PS exhibited significant photodynamic activity with 5-6 logs reduction in bacterial load was achieved.

Development of superior heterogeneous photocatalyst for hydrogen (H2) evolution with promising pollutant degradable capacity is a significant feature but then again thought-provoking for shaping the energy and environmental issues. In this regard, a photocatalytic H2 evolution using nano diamond (ND) semiconducting materials having pollutant degradable capacity for Rhodamine B dye (RhB) has been rarely reported and hence predicted to the sustainable energy. Productive characteristics such good chemical stability, super hardness, nanometer size, biocompatibility and thermal conductivity, ND is a capable and highly valuable powder physical material. Non-uniform and agglomeration dispersion spread of ND in different solvents are the main problems preventing ND from the wide-use in commercial applications. Upon 535 nm solar light excitation, the fabricated ND sample exhibit remarkable photocatalytic H2 production with a HER of about 400 μmol h−1 than pristine ND (197 μmol h−1). Additionally, this H2 generation dramatically enhances the quantum yield, indicating the H2 terminated sites work as electron reservoirs. Precisely, the kinetic constant pseudo-order of FND for photodegradation of RhB was higher as compared with pristine ND. As such, the results show an important step toward tailor-designed and explain the vital role of FND composites for the rational motifs of fruitful photocatalyst with effective pollutant degradable capability for future demand.

The amorphous structural study of silicon carbide nanowires (SiC-NWs) has drawn strenuous attention in recent years due to their worthwhile properties for wide applications, chiefly in optoelectronics. The facile transformation of crystalline SiC-NWs to amorphous defective SiC-NWs is a challenging task for their broad-scale applications. Herein, we report a fantastic strategy (by applying a 5UDH Pelletron accelerator, located at the National Centre for Physics, Islamabad, Pakistan) for Cu ion implantation (fixed at 10 MeV) on the crystalline SiC-NWs to incorporate them into an amorphous structure. For the defects study, various dose rates of Cu+ ion ranging from 5 × 1015 ions/cm2 to 5 × 1016 ions/cm2 were bombarded on SiC-NWs, and a complete transmutation to the amorphous structure of SiC-NWs under a shelling dose of 8 × 1016 ions/cm2 was observed. This work will provide a better avenue for the structural deformation blueprints of the next-generation nanomaterials. Amorphous structural transformation is explained by collision cascade effects phenomena.

This work reports in-situ ion beam induced luminescence (IBIL) of CaF2 crystals using 2-MeV proton excitation. The in-situ IBIL experiments were carried out at pelletron Tandem accelerator at the National Center for Physics, Islamabad, Pakistan. The spectrophotometry UV–Visible analysis revealed that proton beam induced Ca colloids. Their concentration increases with fluence, and the mean size reaches about 10 nm. The IBIL results showed a wide luminescence band extended from 230 to 450 nm and a new band at about 210 nm, attributed to the self-trapped exciton (STE) decay. It was found that the luminescence intensity increases linearly with dose. From the absorption measurements, indicating the colloid formation in CaF2 by proton irradiation, we believe that the latter colloids are responsible for the luminescence improvement during proton beam irradiation.

The present work reports the in-situ ion beam induced luminescence measurements using 2 MeV proton excitation of LiF single crystal with the aim of obtaining a further insight on F-type centers kinetics and its correlation with the self-trapped exciton (STE). It is found that the STE luminescence intensity decreases from the beginning of irradiation. While the dose-dependent evolution of F3+ and F2 centers reveals three kinetic stages: (i) linear increase from the beginning of irradiation up to 10.1 MGy, followed by (ii) monotonic decrease to 18.1 MGy, and (iii) steady state from 18.1 to 26.2 MGy where the luminescence intensity remains constant. The STE luminescence completely extinguished at high dose; 18.1 MGy in our case. Whereas, the F3+ and F2 luminescence persist and remain constant above 18.1 MGy. The latter behavior revealed in the present study can be useful for LiF application in radiation dosimetry and an imaging detector.

Spinel ferrite based nanoparticle material has been at the forefront of contemporary nanotechnology for use in various industrial and biomedical applications. The preparation and characterization o...

The effect of 5 MeV Cu++ ions irradiation on structural and optical properties of Anatase TiO2 nanoparticles (TiO2-NPs) is investigated. For this purpose, TiO2-NPs are irradiated with different Cu++ ions fluences, ranging from 1 × 1015 to 1 × 1016 ions/cm2 at room temperature. XRD results confirm the Ti3O7 phase appear at the dose of 5 × 1015 ions/cm2 and peak intensity of Ti3O7 phase gradually increases with an increase of Cu++ ions irradiation dose. At the dose of 1 × 1016 ions/cm2 TiO2 Anatase phase were transformed to Rutile phase. Same observations are confirmed from Raman spectroscopy. High resolution transmission electron microscopy (HRTEM) reveals that morphology converted into wavy shape and crystal structure detrioted with increase Cu ion irradiation dose to form vacancy loops and interstitial loops. Scanning electron microscopy (SEM) shows that TiO2-NPs have been fused to form a cluster of nanoparticles at high Cu ion beam dose, while bandgap of TiO2-NPs reduces from 3.19 eV to 2.96 eV as a function of Cu++ irradiation fluence. These phase transformations and crystal damage are the responsible for optical bandgap reduction. The mechanism for the currently observed phase transformation of TiO2 and coalescence of TiO2-NPs are discussed in term of thermal spikes model. Keywords: TiO2 nanoparticles, Cu++ irradiation, Rutile phase, Coalescence of NPs, Bandgap engineering

Electrical conductivity and optical transmittance of nickel nanowire (Ni-NW) networks are reported in this work. The Ni-NWs were irradiated with 3.5, 3.8 and 4.11[Formula: see text]MeV proton (H[Formula: see text]) ions at room temperature. The electrical conductivity of Ni-NW networks was observed to increase with the increase in beam energies of H[Formula: see text] ions. With the increase in ions beam energies, electrical conductivity increases and this may be attributed to a reduction in the wire–wire point contact resistance due to the irradiation-induced welding of NWs. Welding is probably initiated due to H[Formula: see text] ion-irradiation induced heating effect that also improved the crystalline quality of the NWs. After ion beam irradiation, localized heat is generated in the NWs due to ionization which was also verified by SRIM simulation. Optical transmittance is increased with increase in the energy of H[Formula: see text] ions. The Ni-NW networks subjected to an ion beam irradiation to observe corresponding changes in electrical conductivity and optical transparencies are promising for various nanotechnological applications, such as highly transparent and conducting electrodes.

Multi-walled carbon nanotube (MWCNT)/dextran/nano-gold composite was prepared by chemical solution reaction. The average diameter of gold nanoparticles was around 15 nm. MWCNT/dextran/nano-gold composites were uniformly dispersed in aqueous solution as electrode materials. MWCNT/dextran/nano-gold composites exhibited excellent electrochemical property in [Fe(CN)6]3– /4– solution. Experimental results showed that the MWCNT/dextran/nano-gold composites with 50% MWCNTs presented obvious redox peak and low impedance and had good electrochemical response to Cu2+. The redox peak currents were linear while the concentration of copper ions ranged from 1× 10–2 to 1 × 10–4 M. The relationship between oxidation peak currents I (A) and Cu2+ concentration C (M) was: ipk (A) = 2.6207 × 10–6 + 43.91572 × 10–4 × C (M), and the limit of determination (LOD) of Cu2+ was 0.63 × 10–6 M, and linear coefficient was 0.9923.

In this work, short carbon fibers were utilized as reinforcing materials to incorporate with C-SiC ceramics. Cf/C-SiC composites containing diverse fiber contents were fabricated by combining compression molding and hot sintering. Mechanical and tribological properties were carefully investigated. The result indicates that 30 vol% fiber content composite shows the highest flexural strength (201.42 MPa) and shear strength (116.68 MPa). The reinforcing mechanisms are summarized as fiber pulling-out, fiber debonding and fiber bridging, as well as crack deflection. Tribological testing reveals that 30% fiber content composite shows the strongest wear resistance (3.95 × 10−6 mm3/N⋅m) and cyclic performances (COF of 0.27 after 50 cycles). The friction mechanisms are divided into abrasive wear, adhesion wear and oxidation wear by different wear stages.

The development of high dielectric loss and magnetic loss for radar absorbing material is a long-term pursuing and under a close scrutiny. Most of the researches have been focused on exploring absorber materials with good absorption performance and at the same time with a good electrical conductivity. To develop a new absorber material will also have significant impacts on boosting the dielectric loss and magnetic loss. Herein, 3D spherical NiCo2S4 (NCS)-based composite has been fabricated via a mild, simple and useful hydrothermal strategy and the electromagnetic wave absorbing properties have been investigated through comparison among NCS, acidified carbon nanotubes (a-CNT)/NCS, reduced graphene oxide (r-GO)/NCS and r-GO/a-CNT/NCS. The experimental results show that the optimal concentration of NiSO4·6H2O to synthesize the composites is 6 M. Furthermore, the frequency bandwidth has been broadened and the maximum absorption peaks have been increased after adding the modified agent. The maximum frequency bandwidth of r-GO/a-CNT/NCS is 5.1 GHz below −5 dB and 2.7 GHz below −10 dB respectively, the maximum absorption peak is −35.8 dB at 8.1 GHz.

To improve the mechanical properties and oxidation resistance of short carbon fiber reinforced silicon carbide matrix composites, carbon nanotubes (CNTs) were grown in-situ on carbon fiber surfaces through continuous CVD, a small amount of phenolic formaldehyde (PF) was added to the matrix to densify the composite and interlock the fiber and the matrix. The CNTs-Cf/PF/SiC composite was fabricated by combining pre-casting and hot-pressing. Microstructural analyses revealed that CNTs were successfully grown on carbon fiber surfaces with entangled structures, while PF presented cobweb-like structure which tightly bonded the fiber and the matrix. Compared with CNTs-Cf/SiC and Cf/SiC, the flexural strength of CNTs-Cf/PF/SiC increased by 15.27% and 51.95%. After heat treatment, the weight loss of CNTs-Cf/PF/SiC reached 21.05%, and 31.9% of flexural strength retained after 15 thermal shock cycles at 1400 °C. These enhanced properties were indicative of its enormous potential to replace traditional Cf/SiC composite.

In this work, a high-performance electrode material has been fabricated by the incorporation of carbon nanotubes (CNTs) and polyaniline (PANI) on a carbon foams (CF) to improve its electrochemical performance. The microstructure and performance of as-prepared material was characterized in detail. Results showed that the resultant material exhibited a high gravimetric capacitance up to 467.1 F g−1, higher energy density of 104. 2 Wh kg−1 and power density of 3000 W kg−1 at a current density 3 A g−1 when the electrochemical doping time of PANI equals to 20 min. Furthermore, it appeared a good cycling stability with capacitance retention of 94.5% after 10000 cycles. The enhanced electrochemical performance can be attributed to the unique carbon nanostructure and synergistic effects of active materials CNTs and PANI. It indicates that this novel CF/CNTs/PANI-20 composite is a promising candidate for electrochemical capacitors.

In this work, reaction bonded silicon carbide (RBSC) brake composites reinforced by chopped carbon fibers (CCFs) were fabricated by pre-liquid dispersion (PLD), low-temperature compression molding (LTCM) and subsequent densification by liquid silicon infiltration (LSI). The effects of the CCF fraction and PLD process on microstructure, phase composition, compression strength, shear strength and tribological performance of the brake composites were evaluated in detail. Our results showed that the distribution of CCF within the brake composites can be improved substantially through the treatment of PLD process, leading to the lowest open porosity of 9.63% and highest buck density of 1.87 g/cm3 comparing to the composites without PLD. Meanwhile, due to the augment of the interfacial area between the CCF and matrix, the as-prepared brake composite with 20 vol% CCF showed a compression strength as high as 157.55 MPa and shear strength of 22.14 MPa. Moreover, after further graphitization, a highly reliable RBSC brake composite with suitable average friction coefficient (0.427) for braking was obtained via the synergistic effects of lubrication of formed graphite and grain-abrasion by SiC grains in spite of a relatively high mass wear rate. These results show that the CCF reinforced RBSC brake composite is a promising candidate for high performance and low-cost friction composite for the application in brake pads.

Single-walled carbon nanotubes (SWCNTs) were prepared by a modified arc discharge furnace using 500 Torr helium as buffer gas at 600 °C. The effect of the catalyst type on the production of SWCNTs ...