ISSR Polymorphism Analysis of Eight F_1 Hybrids of Erianthus fulvus and Saccharum spp.

In this study, twelve primers were used for ISSR （ inter simple sequence repeat） analysis of eight F1 hybrids of Erianthu.sfulvus and sugarcane （ Saccha- rum spp. ）. The results showed that totally 133 bands were amplified, including 111 polymorphic bands, showing a polymorphic rate of 83.46%, which indicated that there are abundant genetic variations among F1 progenies derived from crossing between cultivated sugarcane and E. fu/vus. The average genetic similarity coef- ficients between F1 progenies and female parent Yacheng 89-9, F1 progenies and male parent E. fidvas were 0.67 and 0.44, respectively. UPGMA clustering result of F1 progenies showed that all the progenies were clustered with female parent, suggesting that the genetic material of female parent was predominated in F： proge- nies, which also revealed that the chromosome number of F, progenies was not directly related to the clustering results based on ISSR analysis.

Chromosomal Transmission in F_2BC_1Hybrid Progenies between Sugarcane and Erianthus fulvus

[ Objective ] This study aimed to provide a scientific basis for breeding new sugarcane varieties with hybrid progenies of Erianthus fulvus and modifying existing sugarcane cultivars. [ Method] Chromosomal slides of the F2 and F2 BC1 hybrid progenies between sugarcane and E. fu/vus （2n = 20） and those of parental materials were prepared with the wall degradation hypotonic method, to further analyze the chromosomal transmission in the F2 and F2BC1 hybrid progenies and to investigate the chromosome transmission mechanism. [ Result ] The results showed that, somatic chromosome number varied in various hybrid progenies; chromo- somes from parents were transmitted into the somatic cells of F2 hybrids in ＂2n ＋ n＂ pattern and transmitted into the somatic cells of F2BC1 hybrids in ＂n ＋ n＂ pattern. [ Conclusion ] This study provided a preliminary cytological basis for further use of these materials in sugarcane breeding.

Karyotype Analysis of BC_1 and BC_2 Progenies between Sugarcane and Erianthus fulvus

In this study, karyotype analysis of F2BCl progenies between sugarcane （Saccharum spp. ） and Erianthusfulvus was conducted. The result showed that most chromosomes of YAU04/14, YAU09/02, YAU09/05, YAU09/26 and YAU09/52 are median region （m） chromosomes, while only a small amount of chromosomes are submedian （sin） chromosomes and median point （M） chromosomes. The karyotype formulae of five experimental materials are 2n = 106 = 98m ＋ 8sm, 2n = 106 - 2M ＋ 104m, 2n = 106 = 4M ＋ 96m ＋ 6sin, 2n = 102 = 2M ＋ 92m ＋ 8sin and 2n = 106 = 4M ＋ 96m ＋ 6sin, respectively. The karyotypes of all materials belong to symmetrical 2B type, indicating that the chromosomes of progenies are primitive.

Karyotype Comparison of F_1 and F_2 Hybrids of Sugarcane and Erianthus fulvus

Chromosome specimens of sugarcane, Erianthus fu/vus and their progenies were prepared with wall degradation hypotonic method to analyze the karyotypes of parents and Fl, F2 hybrids. The results showed that most chromosomes of experimental materials are median region （m） chromosomes, while only a small amount of chromosomes are submedian （sm） chromosomes. The karyotype of YAU04/102 belongs to 2C type, while other materials belong to 2B type. In addition, the karyotypes of hybrids are asymmetrical and the chromosomes of hybrids show an evolutionary trend compared with parental chromosomes.

Evaluation of Cold Tolerance in Wild Sugarcane Germplasm Resources under Field Conditions

In January 2016, Kunming underwem 52 hours of rain and snow weather below 0℃. in order to identify the cold tolerance of different wild sugarcane germplasm resources in low temperature and snow disasters, cold injuries of 38 shares of wild sugareane germplasm resources, which were oollected during 2012 -2013 and preserved in the germplasm resource nursery of Sugarcane Research Institute, Yumlan Agricultural University, were surveyed to evaluate the cold tolerance based on sugarcanc cold tolerance index （CTI） = 0.5 x shoot tip growing point injury index ＋ O. 3 x node injury index ＋ 0.2X internode injury in- dex. The results showed that cold tolerance indexes of four wild sugarcane varieties demonstrated a descending order of Erianthus arundinaceum Retz. （0.7）, Eri- aTrthus rockii Keng （0.5） , Sacchartun sporrtanettm L. （0.3） , Erianlhus fulvus Ne^s. （0）. Greater cold tolerance indexes indicate poorer cold tolerance. Thus, Erianthu, arundinaceum had the poorest cold tolerance, while Erianthus fulvus exhibited the strongest cold tolerance. In addition, there were significant differences in cold tolerance among diffcrent Saccharum spontaneum clones. The 23 Saccharum spontaneum clones could be divided into four grades, including 1 clone with the poorest cold tolerance that accounted for 4.3%, 5 clones with poor cold tolerance that accounted for 21.7%, 14 clones with strong cold tolerance that accounted tot 60.9%, and 3 clones with the strongest cold tolerance that accounted for 13.0% （2012 -23, 2012 -32, 2012 -37）. Especially, 2012 -23 exhibited extremely strong cold tolerance. This study provided the scientific basis for screening of cold-tolerant wild sugarcane germplasm resources and selection of cold-toleranl parents.

Polymeric aluminum porphyrin:Controllable synthesis of ultra-low molecular weight CO_(2)-based polyols

Carbon dioxide-based polyols with ultra-low molecular weight(ULMW,Mn<1000 g/mol)are emergent polyurethane precursors with economic and environmental benefits.However,the lack of effective proton-tolerant catalytic systems limits the development of this field.In this work,the polymeric aluminum porphyrin catalyst(PAPC)system was applied to the copolymerization of CO_(2)and propylene oxide,where sebacic acid,bisphenol A,poly(ethylene glycol),and water were used as chain transfer agents to achieve the controlled synthesis of CO_(2)-polyols.The molecular weight of the resulting CO_(2)-polyols could be facilely regulated in the range of 400–930 g/mol at low catalyst loadings,fully demonstrating its catalytic advantages of high activity,high product selectivity,and excellent proton tolerance of PAPC.Meanwhile,the catalytic efficiency of PAPC could reach up to 2.1–5.2 kg/g under organic CTA conditions,even reaching 1.9 kg/g using water as the CTA.The cPC content could be controlled within 1.0 wt%under the optimized conditions,indicating the excellent controllability of the PAPC system.ULMW CO_(2)-polyols combines the advantages of low viscosity(∼3000 mPa s at 25°C),low glass transition temperature(∼−73°C),and high carbonate unit content(∼40%),which is important for the development of high-performance polyurethanes.

Polymeric catalyst with polymerization-enhanced Lewis acidity for CO_(2)-based copolymers

Ring-opening copolymerization of CO_(2) and epoxides is a promising way to manufacture high value-added materials.Despite a variety of catalyst systems have been reported,the reaction is still limited by low activity and polymer selectivity.Herein,a strategy of polymerization-enhanced Lewis acidity is reported to construct a series of highly efficient polymeric aluminum porphyrin catalysts(PAPCs).The characterization of the coordination equilibrium constant(K_(eq))showed significantly enhanced Lewis acidity of PAPC(K_(eg)=18.2 L/mol)compared to the monomeric counterpart(K_(eq)=6.4 L/mol),accompanied with increased turnover frequency(TOF)from 136 h^(-1) to 5500 h^(-1).Through detailed regulation of Lewis acidity,the highly Lewis acidic PAPC-OTs displayed a record high TOF of 30,200 h^(-1) with polymer selectivity of up to 99%.

Unity Makes Strength:Constructing Polymeric Catalyst for Selective Synthesis of CO_(2)/Epoxide Copolymer

Catalyst design strategies such as bi-functional and di-nuclear catalysts have been developed based on intramolecular interactions,achieving excellent catalytic performance.However,most of these catalysts work in a state of disunity.To make progress in this direction,we reckoned that enhancing the neglected intermolecular interactions of these catalysts might be a suitable approach.Herein,we report a strategy of constructing homogeneous polymeric catalysts based on the philosophy of“unity makes strength”to convert the intermolecular interactions into stronger intramolecular interactions.We united discrete active centers of aluminum(Al)porphyrin and tertiary amine(methyl methacrylate;MMA)via a random copolymerization process into one polymer chain with the subsequent metallization using low-toxic metal AlEt_(2)Cl,to construct polymeric catalysts for selective copolymerization of CO_(2)/epoxide.The spatial confinement enabled the multiple interactions among the active centers,which was distinct from the“point-to-point”interacting systems such as binary,bi-functional,or di-nuclear complexes.Through detailed tuning of the multiple synergistic effects between porphyrin/porphyrin(metal synergistic effect)and Al porphyrin/tertiary amine(Lewis pair effect),the optimized polymeric catalyst showed significantly boosted catalytic activity of 4300 h^(−1),much higher than their mono-nuclear(∼0 h^(−1))and homo-polymeric(750 h^(−1))counterparts.Our present approach for designing polymeric catalysts based on multiple synergistic effects provides a platform for developing highly active catalysts.

Rational design of AIE-active biodegradable polycarbonates for high-performance WLED and selective detection of nitroaromatic explosives

Luminescent polymers have garnered considerable research attention for their excellent properties and wide range of applications in multi-responsive materials,bioimaging,and photoelectric devices.Thereout,various modulations of polymer structure are often the main approach to obtaining materials with different luminescent colors and functions.However,polymers with biodegradability,tunable color,and efficient emission simultaneously remain a challenge.Herein,we report a feasible strategy to achieve degradable and highly emissive polymers by exquisite combination and interplay of aggregation-induced emission(AIE)unit and environmental-friendly epoxide/CO_(2)copolymerization.A series of polycarbonates P-TEP_(x)CN_(y)(x=0,1,2,4,30,120;y=0,1)were prepared,with emission color changed from blue to yellow by controlling the proportion of two designed AIE-active monomers.Among them,Using P-TCN as emitting layer,high performance white light-emitting diode(WLED)device with an external quantum efficiency(EQE)of 26.09%and CIE coordinates of(0.32,0.32)was achieved.In addition,the designed polymers can be used as selective sensors for nitroaromatic compounds in their nanoaggregate states.

A chromosome-level genome assembly for Erianthus fulvus provides insights into its biofuel potential and facilitates breeding for improvement of sugarcane

Erianthus produces substantial biomass,exhibits a good Brix value,and shows wide environmental adaptability,making it a potential biofuel plant.In contrast to closely related sorghum and sugarcane,Erianthus can grow in degraded soils,thus releasing pressure on agricultural lands used for biofuel production.However,the lack of genomic resources for Erianthus hinders its genetic improvement,thus limiting its potential for biofuel production.In the present study,we generated a chromosome-scale reference genome for Erianthus fulvus Nees.The genome size estimated by flow cytometry was 937 Mb,and the assembled genome size was 902 Mb,covering 96.26%of the estimated genome size.A total of 35065 proteincoding genes were predicted,and 67.89%of the genome was found to be repetitive.A recent wholegenome duplication occurred approximately 74.10 million years ago in the E.fulvus genome.Phylogenetic analysis showed that E.fulvus is evolutionarily closer to S.spontaneum and diverged after S.bicolor.Three of the 10 chromosomes of E.fulvus formed through rearrangements of ancestral chromosomes.Phylogenetic reconstruction of the Saccharum complex revealed a polyphyletic origin of the complex and a sister relationship of E.fulvus with Saccharum sp.,excluding S.arundinaceum.On the basis of the four amino acid residues that provide substrate specificity,the E.fulvus SWEET proteins were classified as monoand disaccharide sugar transporters.Ortho-QTL genes identified for 10 biofuel-related traits may aid in the rapid screening of E.fulvus populations to enhance breeding programs for improved biofuel production.The results of this study provide valuable insights for breeding programs aimed at improving biofuel production in E.fulvus and enhancing sugarcane introgression programs.

二氧化碳共聚物的合成与性能研究

二氧化碳是一种来源丰富、价格低廉的可再生C1资源,以其为原料可合成两类高分子材料,即二氧化碳基塑料(PPC)和二氧化碳基聚氨酯(CO_2-PU),这已经成为二氧化碳化学利用领域的重要发展方向.本文总结了中国科学院长春应用化学研究所20年来在二氧化碳共聚物合成及性能调控方面的研究进展,分析了目前二氧化碳共聚物研究所面临的挑战,并对其未来发展前景进行了预测.

Temperature-responsive Catalyst for the Coupling Reaction of Carbon Dioxide and Propylene Oxide

The selective synthesis of polypropylene carbonate （PPC） and cyclic propylene carbonate （CPC） from coupling reaction of CO_2 and propylene oxide （PO） is a long term pursuing target. Here we report that a temperature controllable porphyrin aluminum catalyst using 5,10,15,20-tetra（1,2,3,4,5,6, 7,8-octahydro-1,4：5,8-dimethanoanthracen-g-yl）porphyrin as ligand, once in conjunction with suitable onium salt, achieved single cycloaddition or co- polymerization reaction. Only cydoaddition reaction happened at temperature above 75 ℃ to produce 100% CPC, whereas copolymerization became dominant to afford PPC with selectivity over 99% at 25℃, and the obtained PPC showed over 99% carbonate linkage and 92% head-to-tail structure. Based on systematic analysis of the electronic and steric feature in the porphyrin ligand, it was found that the electronic feature of the substituent in porphyrin ligand was decisive for PPC selectivity, porphyrin ligand bearing strong electron-donating substituents displayed a significantly reduced toler- ance towards increased temperature with respect to PPC formation. Therefore, temperature-responsive catalyst could be designed by suitable modifica- tion in porphyrin ligand, and such accurate synthesis of target product by one catalyst may create a useful and facile platform for selective PPC or CPC production.

Environmentally benign metal catalyst for the ring-opening copolymerization of epoxide and CO_(2): state-of-the-art, opportunities, and challenges

Carbon dioxide(CO_(2))is the main greenhouse gas,whereas it is also a nontoxic,abundant,cheap carbon and oxygen resource.The copolymerization of CO_(2) with epoxide presents a sustainable approach to the synthesis of biodegradable polymers,which upcycles the waste into wealth.Metal complex catalyst plays the central role in the reaction,since it provides oxophilic and Lewis acidic active center both for monomer activation and chain end stabilization,and nucleophiles as Lewis base for initiation.However,heavy metal catalyst with certain toxicity such as cobalt undisputedly dominates the copolymerization catalysis which comprises the overall sustainability.To circumvent the potential environmental hazard,developing highly active catalyst composed of green metals is of great importance especially when the polymer was utilized for agriculture purpose.This work reviews the development of sustainable metal catalysts for the production of CO_(2) copolymer,centered by Al,Mg,Ti,Fe,generally acknowledged as low toxic,environmentally benign,biocompatible,and also abundant in earth's crust.Emphasis is placed in recent five years where several historic examples are also included to construct a full picture of the sustainable catalysis explored to date.

Construction of Self-Reporting Biodegradable CO_(2)-Based Polycarbonates for the Visualization of Thermoresponsive Behavior with Aggregation-Induced Emission Technology

Thermoresponsive polymers with simultaneous biodegradability and signal“self-reporting”outputs that meet for advanced applications are hard to obtain.To address this issue,we developed fluorescence signal“self-reporting”biodegradable thermoresponsive polycarbonates through the immortal copolymerization of CO_(2)and oligoethylene glycol monomethyl ether-functionalized epoxides in the presence of hydroxyl-modified tetraphenylethylene(TPE-OH).TPE-OH was used as chain transfer agent to afford well-defined polycarbonates with controlled molecular weight(6000—17000 g·mol^(–1))and aggregation-induced emission characteristics.Through temperature-dependent fluorescence intensity study,low critical solution transition of TPE-labeled polycarbonates were determined and the fine details of thermal-induced phase transition process were monitored.Further research indicated that temperature-controlled aggregation and dissociation of TPE moieties are the main reason for fluorescence intensity variations.We anticipate that this work could offer a method to visualize the thermal transition process of thermoresponsive polycarbonates and broaden their application fields as smart materials.

Carbon dioxide copolymers:Emerging sustainable materials for versatile applications

Carbon dioxide(CO_(2))is cheap,renewable,abundant,and nontoxic carbon feedstocks in chemical reactions.In the past two decades,utilization of CO_(2)in polymer science has become a meaningful topic bridging two separate subjects,namely CO_(2)valorization and sustainable polymer synthesis.This review summarizes the recent progress in CO_(2)copolymer materials from synthesis to material performance adjustment,focusing on commercialized or potential commodity sustainable materials such as biodegradable polycarbonates and new structure polyurethanes from CO_(2)-polyol building blocks.

Controlled synthesis of CO_2-diol from renewable starter by reducing acid value through preactivation approach

Synthesis of polyols from carbon dioxide（CO2） is attractive from the viewpoint of sustainable development of polyurethane industry;it is also interesting to adjust the structure of the CO2-polyols for versatile requirement of polyurethane.However,when renewable malonic acid was used as a starter,the copolymerization reaction of CO2 and propylene oxide（PO） was uncontrollable,since it proceeded slowly（13 h） and produced 40.4 wt%of byproduct propylene carbonate（PC） with a low productivity of 0.34kg/g.A careful analysis disclosed that the acid value of the copolymerization medium was the key factor for controlling the copolymerization reaction.Therefore,a preactivation approach was developed to dramatically reduce the acid value to 0.6mg（KOH）/gby homopolymerization of PO into oligo-ether-diol under the initiation of malonic acid,which ensured the controllable copolymerization,where the copolymerization time could be shortened by 77%from 13 to 3 h,the PC content was reduced by 76%from 40.4 wt%to 9.4 wt%,and the productivity increased by 61%from 0.34 to 0.55 kg/g.Moreover,by means of preactivation approach,the molecular weight as well as the carbonate unit content in the CO2-diol was also controllable.

In situ molecular level visualization of RAFT polymerization by AIEgen-labelled agents

Can we see clearly the whole polymerization process?Normally, it is difficult and thus is a dream for researchers in polymer science. That is why techniques for monitoring the polymerization process have always been a major focus in both academic and industrial field owing to their potential for quality control and process optimization. Several methods,such as rheometry, viscometry and dilatometry, have been developed to study the kinetics of polymerization process.However, these methodologies examine only the macroscopic viscosity instead of at the molecular level.

Chain-transfer-catalyst: strategy for construction of site-specific functional CO_(2)-based polycarbonates

Site-specific functional polymers are generally synthesized from functionalized chain transfer agents(CTA)in the presence of catalysts.However,the poor solubility or chemical inertness of CTAs may make polymerizations uncontrollable.Now,this issue is addressed by proposing a strategy of designing chain-transfer-catalyst(CTC)that combines catalyst and CTA into one.The occurrence of catalytic effect naturally triggers the chain transfer process to give catalyst-labeled polymers with well-defined structures.As a proof-of-concept,cobalt(III)porphyrin catalysts with one,two and four hydroxyl groups act as efficient CTCs,giving the corresponding site-specific functional poly(propylene carbonate)s(PPC),diversifying the topology of polymers.Furthermore,porphyrin-capped PPCs with controllable Mn in the range of 1,000–16,800 g mol^(-1)were obtained by using monofunctional CTC(CTCOH).Moreover,different from traditional“catalyst+CTA”systems,a novel dynamic network transfer mechanism of CTCOH was proposed.This study provides a CTC strategy for the synthesis of site-specific functional polymers.