Tauqeer Ahmad is a Ph.D. candidate in Electronics Science and Technology at Huazhong University of Science and Technology (HUST). His research focuses on the development and characterization of advanced microwave dielectric ceramics and ferroelectric materials for next-generation electronic devices. He is conducting his doctoral work under the supervision of Prof. Wen-Zhong Lu, with co-supervision from Prof. Wen Lei and Dr. Burhan Ullah. Mr. Ahmad holds an M.Phil. in Material Physics from Hazara University and a B.S. in Physics from Islamia College University Peshawar. He is a recipient of the HUST Academic Excellence Award (2022-2023).
Professor Lei Wen is a Researcher and Doctoral Supervisor at the School of Optical and Electronic Information, Huazhong University of Science and Technology (HUST). In addition to his primary role, he serves as the Deputy Director of the HUST Wenzhou Advanced Manufacturing Technology Research Institute, bridging academia and industry. Prof. Lei is actively involved in several key national academic and industrial committees, including as a Council Member of the China Industry-University-Research Collaboration Innovation Platform for Electronic Materials and Components and a Member of the Professional Committee on Key Materials and Technologies for Electronic Components. He also holds editorial positions, serving on the editorial boards of the SCI-indexed journals Journal of Inorganic Materials and Crystals, and contributing to the compilation of the Silicate Dictionary (Second Edition).
Dr. Burhan Ullah holds a Ph.D. in Materials Science from Huazhong University of Science and Technology (HUST), which he obtained under the supervision of Professors Wen-Zhong Lu and Wen Lei. He previously earned an M.Phil. in Material Science from Islamia College University Peshawar and a B.S. in Physics from the University of Peshawar. He recently completed a postdoctoral fellowship in the group of Prof. Daniel Tan at the Guangdong Technion - Israel Institute of Technology. His research interests include the development of microwave dielectric ceramics and ferroelectric materials for electronic devices. Dr. Ullah has published more than 30 papers in international journals and is a recipient of the HUST Academic Excellence Award and the HUST Honorary Award for International Graduates.
Prof. Wenzhong Lu serves as the Deputy Dean of the School of Optical and Electronic Information at Huazhong University of Science and Technology (HUST). Recognized as a New Century Excellent Talent by the Ministry of Education, he has conducted research abroad at Moscow State University and the University of Manchester. With a long-standing focus on electronic information materials and components, his work has led to numerous applied and industrialized technologies. Professor Lu has secured and led more than 20 major national projects, such as those from the National Natural Science Foundation of China and the 863 Program. His scholarly output includes over 200 papers, nearly 30 authorized invention patents, and five significant awards, notably the Second Prize of the National Scientific and Technological Progress Award. An accomplished educator, he is the chief editor of the textbook Electronic Materials Physics (Second Edition) and has guided over 60 doctoral and master's students to completion.
A series of (Sr0.4Ce0.4)TiO3 + 4% (in mass) Sr2CeO4 + x% B2O3 (SCTO + 4% SCO + x% B2O3 for 1≤ x ≤ 5) composites were synthesized via solid-state reaction to investigate the effects of Sr2CeO4 and B2O3 additives on their structural evolution and microwave dielectric properties. X-ray diffraction (XRD) and Rietveld refinement confirmed the dominant orthorhombic phase (O-phase), with SCO as a secondary phase, indicating a chemically stable composite system. HRTEM and SAED analyses further confirmed the formation of the O-phase through direct observation of the superlattice reflections. Microstructural evolution demonstrated B2O3-assisted liquid-phase sintering, reducing porosity (0.017 → 0.006) and increasing grain size (3.34 → 6.01 μm) with increasing x% (in mass). Raman spectroscopy verified octahedral tilting and Ce-O stretching, while B2O3 incorporation modified the TiO6 network via BO3/BO4 interactions. The εr decreased from 113 (SCTO) to 27 at x = 5%, while τf improved from +213 to +12 × 10-6/℃. The reduction in εr arises from a complex interplay of internal factors (ionic polarizability) and external factors (porosity, and density), whereas the variation in τf is governed by compensating effects from Sr2CeO4 and B2O3. Optimal microwave performance was achieved at x = 5%, with Q×f = 43,603 GHz, εr = 27, and τf of +12 × 10-6/℃. The study demonstrates that SCO and B2O3 act as effective modifiers, enhancing densification and dielectric properties in SCTO-based microwave ceramics.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |