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High power cladding-pumped low quantum defect Raman fiber amplifier

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Photonics Research 2024年第5期12卷 995-1003页

作者： YANG ZHANG JIANGMING Xu JUNRUI LIANG SICHENG LI JUN YE XIAOYA MA TIANFU YAO zhiyong pan JINYONG LENG PU ZHOU College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China Nanhu Laser Laboratory National University of Defense TechnologyChangsha 410073China Hunan Provincial Key Laboratory of High Energy Laser Technology National University of Defense TechnologyChangsha 410073China

Heat generated by the quantum defect(QD)in optically pumped lasers can result in detrimental effects such as mode instability,frequency noise,and even catastrophic damage.Previously,we demonstrated that boson-peakbased Raman fiber lasers have great potential in low QD laser generation.But their power scalability and heat load characteristics have yet to be investigated.Here,we demonstrate a boson-peak-based Raman fiber amplifier(RFA)with 815 W output power and a QD of 1.3%.The low heat generation characteristics of this low QD RFA are demonstrated.Both experimental and simulation results show that at this power level,the heat load of the low QD RFA is significantly lower than that of the conventional RFA with a QD of 4.8%.Thanks to its low heat generation characteristics,the proposed phosphosilicate-fiber-based low QD RFA provides an effective solution for the intractable thermal issue in optically pumped lasers,which is of significance in reducing the laser’s noise,improving the laser’s stability and safety,and solving the challenge of heat removing.

关键词： pumped fiber amplifier

Pilot Test of Preparing 2-Alkylanthraquinone Using Alkylation-Oxidation Technology

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 88-97页

作者： Zheng Bo Qian Jianguo Shi Peng pan zhiyong Qie Siyuan Zhang Yueqin Fei Jianqi Qiao Liang Zong Baoning SINOPEC Research Institute of Petroleum Processing Co. LtdBeijing 100083 Shijiazhuang United Petrochemical Co. LtdShijiazhuang 050011

To expedite the development of industrial technology for producing 2-alkylanthraquinone,a novel pilot test of alkylation-oxidation technology was conducted.The process mainly included anthracene alkylation,separation of anthracene and 2-alkylanthracene,oxidation of 2-alkylanthracene,and product purification.Optimal alkylation conditions yielded a 91.1%conversion of anthracene and a 71.73%selectivity for 2-alkylanthracene.To address the separation problem of anthracene and 2-alkylanthracene,solvent-assisted distillation technology was developed,resulting in a 98.9%purity of 2-alkylanthracene and a 91.82%separation yield.When the molar ratio of H2O_(2) to 2-alkylanthracene was 7:1,a 98.96%conversion of 2-alkylanthracene and a 99.94%selectivity for 2-alkylanthraquinone were achieved.A novel composition of 2-alkylanthraquinone,including 2-tert-butylanthraquinone,2-tert-amylanthraquinone,and 2-hexylanthraquinone,was developed.This composition could be effectively separated and purified through a combination of crystallization and washing processes.The elemental composition of the product met the existing standards,and its hydrogenation performance closely matched that of commercially available 2-tert-amylanthraquinone products.

关键词： anthracene 2-alkylanthracene 2-alkylanthraquinone alkylation oxidation hydrogen peroxide

Functional Fibers and Functional Fiber‑Based Components for High‑Power Lasers

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Advanced Fiber Materials 2023年第1期5卷 59-106页

作者： Xiao Chen Tianfu Yao Liangjin Huang Yi An Hanshuo Wu zhiyong pan Pu Zhou College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China

The success of high-power fiber lasers is fueled by maturation of active and passive fibers,combined with the availability of high-power fiber-based components.In this contribution,we first overview the enormous potential of rare-earth doped fibers in spectral coverage and recent developments of key fiber-based components employed in high-power laser systems.Subsequently,the emerging functional active and passive fibers in recent years,which exhibit tremendous advantages in balancing or mitigating parasitic nonlinearities hindering high-power transmission,are outlined from the perspectives of geo-metric and material engineering.Finally,novel functional applications of conventional fiber-based components for nonlinear suppression or spatial mode selection,and correspondingly,the high-power progress of function fiber-based components in power handling are introduced,which suggest more flexible controllability on high-power laser operations.

关键词： High-power laser Laser fiber Passive fiber-based component Functional fiber Functional fiber-based component

Advances in the Immunotherapeutic Potential of Isocitrate Dehydrogenase Mutations in Glioma

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Neuroscience Bulletin 2022年第9期38卷 1069-1084页

作者： Feng Tang zhiyong pan Yi Wang Tian Lan Mengyue Wang Fengping Li Wei Quan Zhenyuan Liu Zefen Wang Zhiqiang Li Brain Glioma Center and Department of Neurosurgery Wuhan University Zhongnan HospitalWuhan430071China Department of Physiology Wuhan University School of Basic Medical SciencesWuhan430071China

Isocitrate dehydrogenase(IDH)is an essential metabolic enzyme in the tricarboxylic acid cycle(TAC).The high mutation frequency of the IDH gene plays a complicated role in gliomas.In addition to affecting gliomas directly,mutations in IDH can also alter their immune microenvironment and can change immune-cell function in direct and indirect ways.IDH mutations mediate immune-cell infiltration and function by modulating immune-checkpoint gene expression and chemokine secretion.In addition,IDH mutation-derived D2-hydroxyglutarate can be absorbed by surrounding immune cells,also affecting their functioning.In this review,we summarize current knowledge about the effects of IDH mutations as well as other gene mutations on the immune microenvironment of gliomas.We also describe recent preclinical and clinical data related to IDH-mutant inhibitors for the treatment of gliomas.Finally,we discuss different types of immunotherapy and the immunotherapeutic potential of IDH mutations in gliomas.

关键词： IDH mutation Tumor immune microenvironment Immunotherapy Glioma

Cladding-pumped Raman fiber laser with 0.78%quantum defect enabled by phosphorus-doped fiber

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High Power Laser Science and Engineering 2022年第2期10卷 1-6页

作者： Xiaoya Ma Jiangming Xu Jun Ye Yang Zhang Liangjin Huang Tianfu Yao Jinyong Leng zhiyong pan Pu Zhou College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073 China

The quantum defect(QD)is an important issue that demands prompt attention in high-power fiber lasers.A large QD may aggravate the thermal load in the laser,which would impact the frequency,amplitude noise and mode stability,and threaten the security of the high-power laser system.Here,we propose and demonstrate a cladding-pumped Raman fiber laser(RFL)with QD of less than 1%.Using the Raman gain of the boson peak in a phosphorus-doped fiber to enable the cladding pump,the QD is reduced to as low as 0.78%with a 23.7 W output power.To our knowledge,this is the lowest QD ever reported in a cladding-pumped RFL.Furthermore,the output power can be scaled to 47.7 W with a QD of 1.29%.This work not only offers a preliminary platform for the realization of high-power low-QD fiber lasers,but also proves the great potential of low-QD fiber lasers in power scaling.

关键词： cladding pumping lowquantum defect phosphorus-doped fiber Ramanfiber laser

Advances in the slurry reactor technology of the anthraquinone process for H2O2 production

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Frontiers of Chemical Science and Engineering 2018年第1期12卷 124-131页

作者： Hongbo Li Bo Zheng zhiyong pan Baoning Zong Minghua Qiao Research Institute of Petroleum Processing Sinopec Beijing 100083 China Department of Chemistry Fudan University Shanghai 200433 China

This paper overviews the development of the anthraquinone auto-oxidation （AO） process for the pro- duction of hydrogen peroxide in China and abroad. The characteristics and differences between the fixed-bed and fiuidized-bed reactors for the AO process are presented. The detailed comparison indicates that the production of hydrogen peroxide with the fluidized-bed reactor has many advantages, such as lower operation cost and catalyst consumption, less anthraquinone degradation, higher catalyst utilization efficiency, and higher hydrogenation efficiency. The key characters of the production technology of hydrogen peroxide based on the fluidized-bed reactor developed by the Research Institute of Petroleum Proces- sing, Sinopec are also disclosed. It is apparent that substituting the fluidized-bed reactor for the fixed-bed reactor is a major direction of breakthrough for the production technology of hydrogen peroxide in China.

关键词： anthraquinone process fixed-bed reactor slurry-bed reactor hydrogen peroxide

Recent advances in fruit crop genomics

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Frontiers of Agricultural Science and Engineering 2014年第1期1卷 84-90页

作者： Qiang XU Chaoyang LIU Manosh Kumar BISWAS zhiyong pan Xiuxin DENG Key Laboratory of Horticultural Plant Biology(Ministry of Education) Huazhong Agricultural UniversityWuhan 430070China

In recent years,dramatic progress has been made in the genomics of fruit crops.The publication of a dozen fruit crop genomes represents a milestone for both functional genomics and breeding programs in fruit crops.Rapid advances in high-throughput sequencing technology have revolutionized the manner and scale of genomics in fruit crops.Research on fruit crops is encompassing a wide range of biological questions which are unique and cannot be addressed in a model plant such as Arabidopsis.This review summarizes recent achievements of research on the genome,transcriptome,proteome,miRNAs and epigenome of fruit crops.

关键词： fruit crops fruit biology gene function genomics

5 kW-level single-mode fiber amplifier based on low-numerical-aperture fiber

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Chinese Optics Letters 2024年第4期22卷 71-76页

作者：陈益沙叶云黄良金杨欢吴函烁闫志平潘志勇王小林王泽锋周朴 College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China Nanhu Laser Laboratory National University of Defense TechnologyChangsha 410073China Hunan Provincial Key Laboratory of High Energy Laser Technology National University of Defense TechnologyChangsha 410073China

A low-numerical-aperture(NA)concept enables large-mode-area fiber with better single-mode operation ability,which is beneficial for transverse mode instability and nonlinear effects suppression.In this contribution,we reported a high-power fiber amplifier based on a piece of self-developed large-mode-area low-NA fiber with a core NA of 0.049 and a core/inner cladding diameter of 25/400μm.The influence of the pump wavelength and fiber length on the power scaling potential of the fiber amplifier is systematically investigated.As a result,an output of 4.80 kW and a beam quality factor of~1.33 were finally obtained,which is the highest output power ever reported in a fiber amplifier exploiting the low-NA fiber.The results reveal that low-NA fibers have superiority in power scaling and beam quality maintenance at high power levels.

关键词： high power fiber lasers ytterbium-doped fiber low-numerical-aperture fiber mode instability

Transverse mode instability mitigation in a high-power confined-doped fiber amplifier with good beam quality through seed laser control

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High Power Laser Science and Engineering 2022年第6期10卷 84-93页

作者： Hanshuo Wu Haobo Li Yi An Ruixian Li Xiao Chen Hu Xiao Liangjin Huang Huan Yang Zhiping Yan Jinyong Leng zhiyong pan Pu Zhou College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangshaChina

In this work,a confined-doped fiber with the core/inner-cladding diameter of 40/250μm and a relative doping ratio of 0.75 is fabricated through a modified chemical vapor deposition method combined with the chelate gas deposition technique,and subsequently applied in a tandem-pumped fiber amplifier for high-power operation and transverse mode instability(TMI)mitigation.Notably,the impacts of the seed laser power and mode purity are preliminarily investigated through comparative experiments.It is found that the TMI threshold could be significantly affected by the seed laser mode purity.The possible mechanism behind this phenomenon is proposed and revealed through comprehensive comparative experiments and theoretical analysis.Finally,a maximum output power of 7.49 kW is obtained with the beam quality factor of approximately 1.83,which is the highest output power ever reported in a forward tandem-pumped confined-doped fiber amplifier.This work could provide a good reference and practical solution to improve the TMI threshold and realize high-power high-brightness fiber lasers.

关键词： confined-doped fiber fiber laser good beam quality high power transverse mode instability mitigation