Effects of variety and chemical regulators on cold tolerance during maize germination

Maize growth and development is affected by low temperature(LT) especially at the early stages of development. To describe the response of different varieties to LT stress and determine an effective method to cope with LT stress, maize hybrids Zhengdan 958(ZD 958) and Danyu 39(DY 39) were planted and grown at 10 and 25°C, respectively. Effects of the chemicals potassium chloride(KCl), gibberellin(GA), 2-diethylaminoethyl-3,4-dichlorophenylether(DCPTA), and all three combined chemicals(KGD) on coping with LT stress were tested by seed priming. The varieties performed significantly different at 10°C. Compared to leaf, root growth was more severely affected by LT stress. Root/leaf ratio is likely a more reliable parameter to evaluate cold tolerance based on its close correlation with leaf malondialdehyde(MDA) content(R=–0.8). GAadvanced seed germination by about 2 days compared with control treatment of water. GAand DCPTA both resulted in lower leaf MDA content and higher leaf and root area, and root/leaf ratio. KCl resulted in the highest evenness of plant height. KGD performed the best in increasing cold tolerance of maize morphologically and physiologically. Strategies to increase maize tolerance of cold stress, such as variety breeding or chemical selection, would increase maize yield especially at high-latitude regions and have great implications for food security.

Inducing fertility restoration in the genic male sterile line of rice with chemical regulators

For the first time, the fertility of rice genic male sterile line was partially restored with the application of chemical regulators at Hainan Rice Breeding Nursery on Mar 1993. A single panicle of the rice plant could bear as many as 27 grains. The chemical agent that could modulate the growth of the rice plants of genic male sterile line was developed by Prof ZHOU Guangqia and his colleagues at the Biology Institute, Hunan Teachers University, China.

Effect of Chemical Regulation on Maize in Different Cultivation Densities

[Objective] This study aimed at investigating the effect of chemical regulation on maize cultivated in different densities.[Method] By taking maize hybrids Xundan 20 and Zhongnongda 4 as materials,the effect of chemical regulation on the yield,yield component factors and plant morphology of the two hybrids planting in Northern and Northeastern China were studied,respectively.[Result] Chemical Yuhuangjin could control maize stalks,lower the plant height and the ear height,make internodes below the spike more coarse and enhance its lodging-resistance.In addition,chemical regulation could increase the optimum cultivation density by 7 500 plants/hm2 more than traditional cultivation.[Conclusion] This paper provided theoretical reference for cultivating high-yield maize.

Revisiting the Role of Physical Confinement and Chemical Regulation of 3D Hosts for Dendrite-Free Li Metal Anode

Lithium metal anode has been demonstrated as the most promising anode for lithium batteries because of its high theoretical capacity,but infinite volume change and dendritic growth during Li electrodeposition have prevented its practical applications.Both physical morphology confinement and chemical adsorption/diffusion regulation are two crucial approaches to designing lithiophilic materials to alleviate dendrite of Li metal anode.However,their roles in suppressing dendrite growth for long-life Li anode are not fully understood yet.Herein,three different Ni-based nanosheet arrays(NiO-NS,Ni_(3)N-NS,and Ni_(5)P_(4)-NS)on carbon cloth as proof-of-concept lithiophilic frame-works are proposed for Li metal anodes.The two-dimensional nanoarray is more promising to facilitate uniform Li^(+)flow and electric field.Compared with the NiO-NS and the Ni_(5)P_(4)-NS,the Ni_(3)N-NS on carbon cloth after reacting with molten Li(Li-Ni/Li_(3)N-NS@CC)can afford the strongest adsorption to Li+and the most rapid Li+diffusion path.Therefore,the Li-Ni/Li_(3)N-NS@CC electrode realizes the lowest overpotential and the most excellent electrochemical performance(60 mA cm^(−2)and 60 mAh cm^(−2)for 1000 h).Furthermore,a remarkable full battery(LiFePO_(4)||Li-Ni/Li_(3)N-NS@CC)reaches 300 cycles at 2C.This research provides valuable insight into designing dendrite-free alkali metal batteries.

Manipulating the ion-transference and deposition kinetics by regulating the surface chemistry of zinc metal anodes for rechargeable zinc-air batteries

Aqueous zinc-air battery(ZAB)has attractive features as the potential energy storage system such as high safety,low cost and good environmental compatibility.However,the issue of dendrite growth on zinc metal anodes has seriously hindered the development of ZAB.Herein,the N-doped carbon cloth(NC)prepared via magnetron sputtering is explored as the substrate to induce the uniform nucleation of zinc metal and suppress dendrite growth.Results show that the introduction of heteroatoms accelerates the migration and deposition kinetics of Zn^(2+)by boosting the desolvation process of Zn^(2+),eventually reducing the nucleation overpotential.Besides,theoretical calculation results confirm the zincophilicity of N-containing functional group(such as pyridine N and pyrrole N),which can guide the nucleation and growth of zinc uniformly on the electrode surface by both promoting the redistribution of Zn^(2+) in the vicinity of the surface and enhancing its interaction with zinc atoms.As a result,the half-cell assembled with magnetron sputtered carbon cloth achieves a high zinc stripping/plating coulombic efficiency of 98.8%and long-term stability of over 500 cycles at 0.2 mA cm^(-2).And the Coulombic efficiency reached about 99.5%at the 10th cycle and maintained for more than 210 cycles at a high current density of 5.0 mA cm^(-2).The assembled symmetrical battery can deliver 220 plating/stripping cycles with ultra-low voltage hysteresis of only 11 mV.In addition,the assembled zinc-air full battery with NC-Zn anode delivers a high special capacity of about 429 mAh g_(Zn)^(-1) and a long life of over 430 cycles.The effectiveness of surface functionalization in promoting the transfer and deposition kinetics of Zn^(2+) presented in this work shows enlightening significance in the development of metal anodes in aqueous electrolytes.

Regulating local chemistry in ZrCo-based orthorhombic hydrides via increasing atomic interference for ultra-stable hydrogen isotopes storage

Developing a universal and reliable strategy for the modulation of composition and structure of energy storage materials with stable cycling performance is vital for hydrogen and its isotopes storage advanced system,yet still challenging.Herein,an ultra-stable lattice structure is designed and verified to increase atomic chaos and interference for effectively inhibiting disproportionation reaction and improving cycling stability in ZrCo-based hydrogen isotopes storage alloy.After screening in terms of configuration entropy calculation,we construct Zr_(1-2)Nb_(x)Co_(1-2x)Cu_(x)Ni_(x)(x=0.15,0.2,0.25) alloys with increased atomic chaos,and successfully achieve stable isostructural de-/hydrogenation during 100 cycles,whose cycling capacity retentions are above 99%,much higher than 22.4%of pristine ZrCo alloy.Both theoretical analysis and experimental evidences indicate the high thermo-stability of orthorhombic lattice in Zr_(0.8)Nb_(0.2)Co_(0.6)Cu_(0.2)Ni_(0.2) alloy.Notably,the increased atomic chaos and interference in Zr_(0.8)Nb_(0.2)Co_(0.6)Cu_(0.2)Ni_(0.2) alloy causes regulation in hydrogen local chemical neighborhood,thereby confusing the hydrogen release order,which effectively eliminates lattice distortion and unlocks an ultrastable lattice structure.This study provides a new and comprehensive inspiration for hydrogen atoms transport behaviors and intrinsic reason of stable orthorhombic transformation,which can contribute to paving the way for other energy storage materials modulation.

Challenges and strategies of chlorine inhibition in anode systems for seawater electrolysis

Seawater electrolysis for green hydrogen production is one of the key technologies for achieving carbon neutrality.However,in anode systems,the chloride ions(Cl^(-))in seawater will trigger an undesired chlorine evolution reaction(CER)that competes with an oxygen evolution reaction(OER),resulting in inferior OER activity and selectivity.Besides,the corrosive Cl^(-)and its derivative products will corrode anodes during seawater electrolysis,leading to poor stability.Therefore,great efforts have been devoted to developing efficient strategies for chlorine inhibition to improve the activity,selectivity,and stability of anode materials.Herein,focusing on chlorine inhibition,we present a mini review to comprehensively and concisely summarize the recent progress in anode systems for boosting seawater electrolysis.In particular,two strategies of physical and chemical regulation to inhibit Cl^(-)are summarized in some representative cases.Finally,some challenges and future opportunities in anode systems for seawater electrolysis are prospected.This mini review aims to shed light on designing highly efficient anode materials for seawater electrolysis.

具有丰富孤对电子的亲锌超分子分子通道实现高度稳定锌阳极

在柔性设备和静态储能电网应用中,可充电水性锌离子电池展现出巨大的潜力.但其发展受到界面不稳定性引起的副反应及枝晶生长的阻碍.本研究中,我们采用了一种新颖的电解液设计,通过含大量孤电子对的亲锌葫芦[7]超分子来应对这一挑战.这些超分子因其独特的分子结构,能够在电化学循环中有效地吸纳和固定Zn离子,从而有效避免了Zn离子的无序迁移和枝晶的形成.超分子中丰富的孤对电子提供的Lewis碱性位点(如叔胺和羰基氧)作为Zn离子的供电子成核位点,促进了紧密成核.这些超分子与Zn离子之间的强烈相互作用,不仅提高了系统的稳定性,还显著抑制了不良副反应.因此,我们组装的对称电池和Zn//V_(2)O_(5)全电池均展示了长效的循环稳定性和卓越的库仑效率.

Chemical regulation of metal halide perovskite nanomaterials for efficient light-emitting diodes

Metal halide perovskite nanomaterials emerged as attractive emitting materials for light-emitting diodes(LEDs) devices due to their high photoluminescence quantum yield(PLQY), narrow bandwidth, high charge-carrier mobility, bandgap tunability, and facile synthesis. In the past few years, it has been witnessed an unprecedented advance in the field of metal halide perovskite nanomaterials based LEDs(Pe LEDs) with a rapid external quantum efficiency(EQE) increase from 0.1% to 14.36%. From the viewpoint of material chemistry, the chemical regulation of metal halide perovskite nanomaterials made a great contribution to the efficiency improvement of Pe LEDs. In this review, we categorize the strategies of chemical regulation as A-site cation engineering, B-site ion doping, X-site ion exchange, dimensional confinement, ligand exchange, surface passivation and interface optimization of transport layers for improving the EQEs of Pe LEDs. We also show the potentials of chemical regulation strategies to enhance the stability of Pe LEDs. Finally, we present insight toward future research directions and an outlook to further improve EQEs and stabilities of Pe LEDs aiming to practical applications.

Stricter regulation applies to antimicrobial substances when used as biocides compared to cosmetics under current EU legislation

Antimicrobial substances are substances that have the ability to kill or slow down the growth of microorganisms such as bacteria,algae and fungi.Exposure of microorganisms to low concentrations of antimicrobial substances may lead to the development of antimicrobial resistance.To protect human health and the environment and to limit resistance,the risks for the release of these substances into the environment should be minimized from all sources.Under the current EU legal framework,some specific uses of antimicrobial substances are strictly regulated whereas others are not.When antimicrobial substances are used as active substances in biocidal products,such as disinfectants,they are regulated by Biocidal Products Regulation.When the same substances are used as preservatives in cosmetic products they fall under Cosmetic Products Regulation.In this paper,we investigated how the regulation of antimicrobial substances differ when used in biocidal products compared to cosmetic products.This was achieved by performing a systematic comparison using document analysis with focus on aims,scope,information requirements,and risk assessment procedures for biocidal active substances and cosmetic preservatives.One of the main differences identified is that no environmental data or environmental risk assessment are required for approval of cosmetic preservatives.In contrast,environmental data and risk assessment for both the active substances and one representative product would be required for the approval of the same substance if used as a biocidal active substance.This means first that a substance not approved for use in biocidal products due to its hazardous environmental properties can still be approved as a cosmetic preservative.And second,the environmental release of antimicrobial substances from cosmetic products remains unassessed and uncontrolled,despite the obvious risks of cosmetic ingredients being emitted into the environment via wastewater.From this,we recommend that an environmental risk assessment is added to the requirements for market approval of cosmetic preservatives to achieve the aim of a high level of protection for the environment as set by several EU regulations.This would be in line with the“one substance e one assessment”approach proposed by the European Commission.While the details of“one substance e one assessment”approach are not decided,it is believed to contribute to more coordinated and transparent chemical safety assessments and enhance interlinking between the regulations.