泥蚶三倍体的诱导研究

2001年5月,用6-DMAP抑制泥蚶受精卵第二极体的释放诱导三倍体的产生。实验采用三个6-DMAP浓度梯度300、450、600μmol/L,三个处理时机即受精卵第一极体排放10、30、50%和三个处理持续时间10、15、20min进行L9(34)正交实验。结果表明6-DMAP对泥蚶三倍体诱导倍化率最高可达90%左右。倍化率最高的组合为6-DMAP浓度 600μmol/L、处理时机受精卵第一极体排放50%、处理持续时间20min。另外本实验还就受精卵发育同步性对泥蚶三倍体倍化率的影响及6-DMAP对泥蚶受精卵的毒性等问题进行了探讨。

三倍体太平洋牡蛎苗种培育研究

报道了2000年9～12月在浙江温岭市东门水产育苗场进行的三倍体太平洋牡蛎苗种培育研究结果。用浓度为70～100μmol/L的6-二甲氨基嘌呤(6-DMAP)诱导受精卵,抑制第二极体的释放,共获得附着稚贝(壳长0.8～1.0mm5712万颗,平均三倍体倍化率为62%。同时讨论了倍化率与诱导时间、效应时间、卵子成熟度之间的关系。

微观孔结构对柔性石墨力学性能的影响

测量了不同密度柔性石墨纸的抗拉强度、压缩率、回弹率和基本断裂功。研究了可膨胀石墨化倍率对其力学性能的影响，又利用ＳＥＭ、ＸＲＤ等分析测试手段研究了柔性石墨的微观孔结构，并探讨了微观孔结构对其力学性能的影响。

柔性石墨板的力学性能与微观结构的关系

测量了不同密度柔性石墨板的拉伸强度、压缩率和回弹率等力学性能。研究了可膨胀石墨膨化倍率对其力学性能的影响 ,认为柔性石墨的抗拉强度主要来自于膨胀石墨解理表面起伏之间相互锁合的机械力———一种内部静摩擦力。又利用SEM、XRD、AFM等分析测试手段研究了柔性石墨的内部微观结构 ,并探讨了微观结构对其力学性能的影响。

Study on Haploid Induction Rates in Different Maize Inducers

[Objective] The aim was to analyze the differences in haploid induction rates of different inducers. [Method] Six maize inducers with purple spot and purple color were selected as the male parents to pollinate six inbred lines. [Result] The mean haploid induction rates were significantly different among the inducers: KMS-3 >WY-1 >PR-2 >YP-13 >KMS-2 >KMS-1. The haploid induction rates of the different hybrid materials were significantly different: K410 >105A >103A >104A >107A >D271 >106A>L73>N21>KZ58. [Conclusion] The haploid inducer line PR-2, which had high haploid induction rate and low variation coefficient, was an elite haploid inducer.

Effect of B and Fe substitution on structure of AB_3-type Co-free hydrogen storage alloy

A series of hydrogen storage Co-free AB3-type alloys were directly synthesized with vacuum mid-frequency melting method,within which Ni of La0.7Mg0.3Ni3 alloy was substituted by Fe,B and(FeB) alloy,respectively.Alloys were characterized by XRD,EDS and SEM to investigate the effects of B and Fe substitution for Ni on material structure.The content of LaMg2Ni9 phase within La0.7Mg0.3Ni3 alloy reaches 37.9% and that of La0.7Mg0.3Ni2.9(FeB)0.1 alloys reduces to 23.58%.Among all samples,ground particles with different shapes correspond to different phases.The major substitution occurs in LaMg2Ni9 phase.Electrochemical tests indicate that substituted alloys have different electrochemical performance,which is affected by phase structures of alloy.The discharge capacity of La0.7Mg0.3Ni3 alloy reaches 337.3 mA·h/g,but La0.7Mg0.3Ni2.9(FeB)0.1 alloy gets better high rate discharge(HRD) performance at the discharge rate of 500 mA/g with a high HRD value of 73.19%.

Interconnected CoS/NC-CNTs network as highperformance anode materials for lithium-ion batteries

Cobalt disulfide(CoS_(2))has been considered a promising anode material for lithium-ion batteries(LIBs)due to its high theoretical capacity of 870 mA h g^(-1).However,its practical applications have been hampered by undesirable cycle life and rate performance due to the volume change and deterioration of electronic conductivity during the dischargecharge process.In this study,an interconnected CoS_(2)/N-doped carbon/carbon nanotube(CoS_(2)/NC-CNTs-700)network was successfully prepared to boost its lithium storage performance,in which small-size CoS_(2)nanoparticles were confined by N-doped carbon and uniformly decorated on the surface of CNTs.N-doped carbon can effectively accommodate the large volume expansion of CoS_(2)nanoparticles.Additionally,the 3D conductive nanostructure design offers adequate electrical/mass transport spacing.Benefiting from this,the CoS_(2)/NCCNTs-700 electrode demonstrates a long cycle life(a residual capacity of 719 mA h g^(-1)after 100 cycles at 0.2 A g^(-1))and outstanding rate performance(335 mA hg^(-1)at 5.0 A g^(-1)).This study broadens the design and application of CoS_(2)and fosters the advances in battery anode research.

A unique co-recovery strategy of cathode and anode from spent LiFePO_(4) battery

Along with the explosive growth in the market of new energy electric vehicles,the demand for Li-ion batteries(LIBs)has correspondingly expanded.Given the limited life of LIBs,numbers of spent LIBs are bound to be produced.Because of the severe threats and challenges of spent LIBs to the environment,resources,and global sustainable development,the recycling and reuse of spent LIBs have become urgent.Herein,we propose a novel green and efficient direct recycling method,which realizes the concurrent reuse of LiFePO_(4)(LFP)cathode and graphite anode from spent LFP batteries.By optimizing the proportion of LFP and graphite,a hybrid LFP/graphite(LFPG)cathode was designed for a new type of dualion battery(DIB)that can achieve co-participation in the storage of both anions and cations.The hybrid LFPG cathode combines the excellent stability of LFP and the high conductivity of graphite to exhibit an extraordinary electrochemical performance.The best compound,i.e.,LFP:graphite=3:1,with the highest reversible capacity(~130 mAhg^(-1) at 25 mAg^(-1)),high voltage platform of 4.95 V,and outstanding cycle performance,was achieved.The specific diffusion behavior of Li^(+) and PF_(6)^(-) in the hybrid cathode was studied using electrode kinetic tests,further clarifying the working mechanism of DIBs.This study provides a new strategy toward the large-scale recycling of positive and negative electrodes of spent LIBs and establishes a precedent for designing new hybrid cathode materials for DIBs with superior performance using spent LIBs.

Porous honeycomb-like C3N4/rGO composite as host for high performance Li-S batteries

Lithium-sulfur (Li-S) batteries have attracted extensive attention along with the urgent increasing demand for energy storage owing to the high theoretical specific capacity and energy density, abundant reserves and low cost of sulfur. However, the practical application of Li-S batteries is still impeded due to the low utilization of sulfur and serious shuttle-effect of lithium polysulfides (LiPSs). Here, we fabricated the porous honeycomb-like C3N4 (PHCN) through a hard template method. As a polar material, graphitic C3N4 has abundant nitrogen content (-58%), which can provide enough active sites to mitigate shuttle-effect, and then conductive reduced graphene oxide (rGO) was introduced to combine with PHCN to form PHCN/rGO composite in order to improve the utilization efficiency of sulfur. After sulfur loading, the PHCN/rGO/S cathode exhibited an initial discharge capacity of 1,061.1 mA h g^-1 at 0.2 C and outstanding rate performance at high current density of 5 C (495.1 mA h g^-1), and also retained 519 mA h g^-1, after 400 cycles at 1 C. Even at high sulfur loading (4.3 mg cm^-2), the capacity fade rate was only 0.16% per cycle at 0.5 C for 200 cycles. The above results demonstrate that the special design of PHCN/rGO composite as sulfur host has high potential application for Li-S rechargeable batteries.

Rational design of viologen redox additives for high-performance supercapacitors with organic electrolytes

Introducing redox species into the electrolytes of traditional electric double layer capacitors(EDLCs)is an efficient strategy to enhance their energy density owing to Faradic reactions.However,few studies have elucidated the effect of the molecular structures of organic redox species on the performance of relative supercapacitors,which is important in the development of redox additives for super-capacitors.In this context,we synthesized several viologens and used them as new organic redox additives for super-capacitors with organic electrolytes.The detailed experimental analysis and theoretical calculation results show that the electrochemical performance of viologens relies heavily on their side chains and conjugated cores.Specifically,the side chains of the viologens affect their electronic structures and are consistent with behaviours between the molecules and the electrode pores due to the size effect,thus influencing their specific capacities.In addition,a larger conjugated aromatic core endows viologens with a smaller band gap and a higher degree of electron delocalization,resulting in better rate performance and cycling stability.Consequently,aπ-conjugated viologen derivative is selected as a favourable additive and enables an EDLC-type supercapacitor to exhibit a high energy density(34.0 W h kg^−1 at 856 W kg^−1)and good cycling performance.

In-situ electropolymerized bipolar organic cathode for stable and high-rate lithium-ion batteries

To address the dissolution issue and enhance the electrochemical performance of organic electrode materials,herein, a bipolar organic cathode was prepared by in-situ electropolymerization of amino-phenyl carbazole naphthalene diimide(APCNDI). APCNDI is composed of n-type 1,4,5,8-naphthalene tetracarboxylic diimide that stores Li cations and p-type carbazole groups which react with anions and serve as polymerization sites. Electropolymerization completely eliminated the dissolution problem of APCNDI, and the electropolymerized cathode demonstrated a bipolar reaction with excellent electrochemical performance, stable cycling performance with a capacity retention of 92 mA h g;after1000 cycles, and a superior rate performance of 72 mA h g;at 10 A g;. The bipolar feature and reactions of APCNDI were systematically investigated and verified by multiple characterization techniques. Our findings provide a novel strategy for the design and fabrication of electrodes for high-performance organic batteries.

Anchoring ultrafine CoP and CoSb nanoparticles into rich N-doped carbon nanofibers for efficient potassium storage

Transition-metal compounds have received extensive attention from researchers due to their high reversible capacity and suitable voltage platform as potassium-ion battery anodes.However,these materials commonly feature a poor conductivity and a large volume expansion,thus leading to underdeveloped rate capability and cyclic stability.Herein,we successfully encapsulated ultrafine CoP and CoSb nanoparticles into rich N-doped carbon nanofibers(NCFs)via electrospinning,carbonization,and phosphorization(antimonidization).The N-doped carbon fiber prevents the aggregation of nanoparticles,buffers the volume expansion of CoP and CoSb during charging and discharging,and improves the conductivity of the composite material.As a result,the CoP/NCF anode exhibits excellent potassium-ion storage performance,including an outstanding reversible capacity of 335mAh g^(-1),a decent capacity retention of 79.3%after 1000 cycles at 1Ag^(-1)and a superior rate capability of 148mAh g^(-1)at 5Ag^(-1),superior to most of the reported transition-metalbased potassium-ion battery anode materials.

Amorphous cobalt hydroxysulfide nanosheets with regulated electronic structure for high-performance electrochemical energy storage

Pseudocapacitors with high power density,longterm durability,as well as reliable safety,play a key role in energy conversion and storage.Designing electrode materials combing the features of high specific capacitance,excellent rate performance,and outstanding mechanical stability is still a challenge.Herein,a facile partial sulfurization strategy has been developed to modulate the electronic structure and crystalline texture of cobalt hydroxide nanosheets(denoted as Co(OH)2)at room temperature.The resultant cobalt hydroxysulfide nanosheet(denoted as Co SOH)electrode with abundant low-valence cobalt species and amorphous structure,exhibits a high specific capacitance of 2110 F g^-1at1 A g^-1with an excellent capability retention rate of 92.1%at10 A g^-1,which is much larger than that of Co(OH)2 precursor(916 F g^-1at 1 A g^-1 and 80%retention at 10 A g^-1).Furthermore,the fabricated asymmetric supercapacitor device constructed with Co SOH and active carbon displays a considerable high energy density of 44.9 W h kg^-1at a power density of 400 W kg^-1,and exceptional stability after 8000cycles.

A Li-rich layered-spinel cathode material for high capacity and high rate lithium-ion batteries fabricated via a gas-solid reaction

Lithium-rich layered oxide(LLO)cathode materials have drawn extensive attention due to their ultrahigh specific capacity and energy density.However,their commercialization is still restricted by their low initial coulombic efficiency,slow intrinsic kinetics and structural instability.Herein,a facile surface treatment strategy via gaseous phosphine was designed to improve the rate performance and capacity stability of LLOs.During the solid-gas reaction,phosphine reacted with active oxygen at the surface of LLOs due to its reductivity,forming oxygen vacancies and spinel phase at the surface region.As a result,Li ion conductivity and structural stability were greatly enhanced.The phosphinetreated LLOs(LLO@P)showed a layered-spinel hybrid structure and delivered an outstanding rate performance of156.7 mA h g^-1 at 10 C and a high capacity retention of 74%after 300 cycles at 5 C.

Boosting the lithium-ion storage performance of perovskite Sr_(x)VO_(3-δ) via Sr cation and O anion deficient engineering

Perovskite SrVO_(3) has been investigated as a promising lithium storage anode where the V cation plays the role of the redox center,combining excellent cycle stability and safe operating potential versus Li metal plating,with limited capacity.Here,we demonstrate the possibility to boost the lithium storage properties,by reducing the non-redox active Sr cation content and fine-tuning the O anion vacancies while maintaining a non-stoichiometric Sr_(x)VO_(3-δ) perovskite structure.Theoretical investigations suggest that Sr vacancy can work as favorable Li^(+) storage sites and preferential transport channels for guest Li^(+) ions,contributing to the increased specific capacity and rate performance.In contrast,inducing O anion vacancy in Sr_(x)VO_(3-δ) can improve rate performance while compromising the specific capacity.Our experimental results confirm the enhancement of specific capacities by fine adjusting the Sr and O vacancies,with a maximum capacity of 444 mAh g^(-1) achieved with Sr_(0.63)VO_(3-δ),which is a 37%increase versus stoichiometric SrVO_(3).Although rich defects have been induced,Sr_(x)VO_(3-δ) electrodes maintain a stable perovskite structure during cycling versus a LiFePO_(4) cathode,and the full-cell could achieve more than 6000 discharge/charge cycles with 80%capacity retention.This result highlights the possibility to use the cation defective-based engineering approach to design high-capacity perovskite oxide anode materials.