Conversion Strategy Research Articles

The Reaction between K2CO3 and Ethylene Glycol in Deep Eutectic Solvents.

Understanding intermolecular interactions is important for the design of deep eutectic solvents. Herein, potassium carbonate (K2CO3) and ethylene glycol (EG) are used to form deep eutectic solvents. The interactions between K2CO3 and EG are studied using nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectra. Interestingly, the interaction results indicate that the carbonate anion CO32- can react with EG to form EG-based organic carbonate, which can occur even at room temperature. The possible reaction steps between K2CO3 and EG are presented. As K2CO3 can be prepared from CO2 and KOH, the findings of this work may provide a promising strategy for CO2 capture and conversion.

Universal design of three-dimensional porous graphene-iron based promotors for kinetically rationalized lithium-sulfur chemistry

Lithium-sulfur (Li-S) batteries are widely deemed to be one of the most potential candidates for future secondary batteries because of their remarkable energy density. Nevertheless, notorious polysulfide shuttling and retarded sulfur reaction kinetics pose significant obstacles to the further application of Li-S batteries. While rationally designed highly active electrocatalysts can facilitate polysulfide conversion, the universal and scalable synthesis strategies need to be developed. Herein, a universal synthetic strategy to construct a series of three-dimensional (3D) porous graphene-iron (3DGr-Fe) based electrocatalysts involving 3DGr-FeP, 3DGr-Fe3C, and 3DGr-Fe3Se4 is exploited for manipulating the Li-S redox reactions. It has been observed that the implementation of a 3D porous Gr architecture leads to the well-designed conductive networks, while the uniformly dispersed iron nanoparticles introduce an abundance of active sites, fostering the lithium polysulfide conversion, thereby bolstering the overall electrochemical performance. The Li-S battery with the 3DGr-Fe based electrocatalyst exhibits remarkable capacity retention of 94.8% upon 100 times at 0.2 C. Moreover, the soft-packaged Li-S pouch cell based on such a 3DGr-Fe electrocatalyst delivers superior capacity of 1060.71 mA h g−1 and guarantees for the continuous 30 min work of fan toy. This investigation gives comprehensive insights into the design, synthesis, and mechanism of 3DGr-Fe based electrocatalysts with high activity toward efficient and durable Li-S batteries.

Planar Deposition via In Situ Conversion Engineering for Dendrite-Free Zinc Batteries.

Owing to the considerable capacity, high safety, and abundant zinc resources, zinc-ion batteries (ZIBs) have been garnering much attention. Nonetheless, the unsatisfactory cyclic lifespan and poor reversibility originate from side reactions and dendrite obstacles to their practical applications. In addition to inhibiting the corrosion of aqueous electrolytes, regulating planar deposition is a key strategy to enhance their long-term stability. Herein, an in situ conversion strategy is reported to construct a protective "dual-layer" structure (VZSe/V@Zn) on zinc metal, consisting of the VSe2-ZnSe outer layer with low lattice mismatch to Zn (002) plane, and corrosion-resistant nanometallic V inner layer. Such design integrates superior interfacial ionic/electronic transfer, corrosion resistance, and unique planar deposition regulation capability. The as-prepared VZSe/V@Zn demonstrates remarkable durability of 238h at 50mA cm-2 with a high depth of discharge (68.3% DOD) in the Zn||Zn symmetric cell. Even in the anode-free system, the as-prepared protective layer can extend the cycle life up to 2000 cycles, with an outstanding capacity retention of 93.1% and ultra-high average coulombic efficiency of 99.998%. This work delineates an effective strategy for fabricating lattice-matching protective layers, with profound implications for elucidating zinc deposition mechanisms and paving the way for the development of high-performance zinc batteries.

Marketing Strategies for Financial MCN Institutions in the Era of Integrated Media

The rapid convergence of multiple types of information carriers in the era of integrated media has given rise to the immediate popularity of short-form videos while enhancing the speed and quality of information dissemination, and the Multi-Channel Network (MCN) Institutions behind them have emerged. With the growth of residents' wealth and the increase in demand for investment and financing, MCN institutions focusing on the financial field are attracting more and more attention from the market. Studying the marketing strategies of financial MCN institutions can help improve their business model and is of great significance in promoting the healthy development of investor education. In this paper, we focus on traffic conversion as an essential link in marketing, summarize the common traffic conversion strategies of financial MCN institutions, analyze the case study of JF Wealth Holdings Ltd., and finally provide corresponding strategic suggestions in terms of customer positioning, traffic retention, traffic conversion, and so on.

Near Sequence Homology Does Not Guarantee siRNA Cross-Species Efficacy.

Small interfering RNAs (siRNAs) represent a novel class of drugs capable of potent and sustained modulation of genes across various tissues. Preclinical development of siRNAs necessitates assessing efficacy and toxicity in animal models. While identifying therapeutic leads with cross-species activity can expedite development, it may compromise efficacy and be infeasible for certain gene targets. Here, we investigate whether deriving species-active siRNAs from potent human-targeting leads-an approach termed mismatch conversion-can yield potent compounds. We systematically altered potent siRNAs targeting human genes associated with diseases-SOD1 (ALS), JAK1 (inflammation), and HTT (HD)-to generate species-matching variants with full complementarity to their target in NHPs, mice, rats, sheep, and dogs. Variants potency and efficacy were measured in corresponding cell lines. We demonstrate that sequence, position, and number of mismatches significantly influence the ability to generate potent species-active compounds via mismatch conversion. Across tested sequences, mismatch conversion strategy ability to identify a species-active lead varied from 0% to 70%. For SOD1, lead compounds identified from species-focus screening in mouse and dog cells were more potent than leads obtained from mismatch conversion. Thus, a focused screening of therapeutic lead and model compounds may represent a more reliable strategy for the clinical advancement of siRNAs.

Platinum-dependent 2H-to-1T phases conversion of MoS2 nanosheets growing on cross-interlocking porous carbon for boosting hydrogen evolution reaction

Proton exchange membrane water electrolysis (PEMWE) coupled with renewable energy is regarded as a sustainable approach for green hydrogen production. However, the low reserve and high cost of platinum cathode electrocatalysts greatly limit its widespread deployment. Herein, we report a phase conversion strategy to obtain an efficient low-Pt loading electrocatalyst composed of multi-atomic Pt substituted 1T-MoS2 nanosheet grown on a cross-interlocking porous carbon matrix (Pt@1T-MoS2/C). In combination with experimental and theoretical results, the 2H-to-1T phase conversion of MoS2 induced by the Pt substitution is investigated, and the as-formed Pt-S-Mo active site accounts for the excellent hydrogen evolution reaction (HER) performance. Benefiting from the improved electron transfer efficiency and Pt-S-Mo active sites, the Pt@1T-MoS2/C delivers a high mass HER activity of ∼58.9 A·mgPt−1, and an excellent stability of 200 h at 1000 mA∙cm−2 in a practical PEMWE device.

Energy analysis during cold start and warm up period of a methanol engine hybrid power system under several novel energy conversion strategies

The use of methanol in engine hybrid power system has a wide range of potential applications, with the primary challenge being cold start issues. This paper innovatively proposes four strategies for starting and warming up the methanol engine, including motor dragging, motor dragging coupled with exhaust gas recirculation (EGR), motor dragging coupled with exhaust control, and motor dragging coupled with both EGR and exhaust control. These strategies can be implemented in methanol hybrid power system with minimal hardware modification costs, and not generate any emissions compared to traditional gasoline assisted strategy. The warm-up mechanisms of these strategies were analyzed and their effectiveness was verified by experiments. The optimum strategy, motor dragging coupling both EGR and exhaust control, has been demonstrated to enhance power input and improve the energy conversion efficiency substantially. Compared to the traditional gasoline assisted strategy, the energy consumption, energy conversion efficiency and the warm-up time in this strategy are 17.9 % lower, 5.1 % higher, 4.2 s shorter, respectively. These strategies well solve the problem of methanol engines being unable to start at low temperatures, which is expected to eliminate the cold start of the engine and directly enter the hot start.

Non-stoichiometric protic ionic liquids for efficient carbon dioxide capture and subsequent conversion under mild conditions

Protic ionic liquids (PILs) have emerged as innovative solvents with significant potential for CO2 capture and transformation, presenting a sustainable alternative to conventional methods which often involve energy-intensive processes or environmentally detrimental chemicals. Herein, a novel strategy for CO2 capture and conversion at mild conditions using non-stoichiometric protic ionic liquids (NPILs) was demonstrated for the first time. These NPILs, employed as sorbents, solvents, and catalysts, were composed of imidazole (Im) and 1,8-diazabicyclo [5.4.0] undec-7-ene (DBU) in various ratios. Correlations between the mole ratio of DBU/Im and physicochemical properties such as viscosity, conductivity, thermal stability, and the distribution of neutral and ionic species were systematically investigated. Effects of the absorption temperature and CO2 partial pressure on the absorption capacity were also studied. Different absorption mechanisms, including carbonate and carbamate pathways, were analyzed using FT-IR and NMR spectroscopy. Moreover, the fixed CO2 could be catalytically converted to quinazoline-2,4(1H,3H)-diones under exceptionally mild reaction conditions (1 atm, 50 °C, metal-free process). A plausible reaction mechanism involving simultaneous CO2 activation and substrate activation for the transformation of CO2 into quinazoline-2,4(1H,3H)-diones was verified through NMR spectra. It is believed that the new insights into the CO2 mechanism will facilitate the rational design of functional ionic liquids for CO2 capture, utilization, and storage in the future.

For aqueous/soil cadmium immobilization under acid attack, does the hydroxyapatite converted from Pseudochrobactrum sp. DL-1 induced vaterite necessarily show higher stability?

Microbial induced carbonate precipitation (MICP) technology was widely applied to immobilize heavy metals, but its long-term stability is tough to maintain, particularly under acid attack. This study successfully converted Pseudochrobactrum sp. DL-1 induced vaterite (a rare crystalline phase of CaCO3) to hydroxyapatite (HAP) at 30 ℃. The predominant conversion mechanism was the dissolution of CdCO3-containing vaterite and the simultaneous recrystallization of Ca4.03Cd0.97(PO4)3(OH)-containing HAP. For aqueous Cd immobilization, stability test at pH 2.0–10.0 showed that the Cd2+ desorption rate of Cd-adsorbed vaterite (3.96–4.35 ‱) were 7.13–20.84 times greater than that of Cd-adsorbed HAP (0.19–0.61 ‱). For soil Cd immobilization under 60 days of acid-rain erosion, the highest immobilization rate (51.00 %) of exchangeable-Cd and the lowest dissolution rate (−0.18 %) of carbonate-Cd were achieved with 2 % vaterite, while the corresponding rates were 16.78 % and 1.31 % with 2 % HAP, respectively. Furthermore, vaterite outperformed HAP in terms of soil ecological thorough evaluation. In conclusion, for Cd immobilization by MICP under acid attack, DL-1 induced vaterite displayed direct application value due to its exceptional stability in soil and water, while the mineral conversion strategy we presented is useful for further enhancing the stability in water.

Photobleaching-mediated charge-convertible cyclodextrin nanoparticles achieve deep tumour penetration for rectal cancer theranostics.

Although charge-converting nanoparticles (NPs) potentially penetrate tumours deeply, conventional charge conversion strategies possess limitations, including low selectivity and slow, inconsistent conversion rate within the tumour microenvironment. In this study, we synthesized a zwitterionic near-infrared cyclodextrin derivative of heptamethine cyanine and complexed it with pheophorbide-conjugated ferrocene to produce multifunctional theranostic nanotherapeutics. Our NPs demonstrated enhanced tumour-targeting ability, enabling the highly specific imaging of rectal tumours, with tumour-to-rectum signal ratios reaching up to 7.8. The zwitterionic surface charge of the NPs was rapidly converted to a cationic charge within the tumours on 880 nm near-infrared laser irradiation, promoting the tumoural penetration of NPs via transcytosis. After penetration, photodynamic/chemodynamic therapy was initiated using a 660 nm laser. Our NPs eradicated clinically relevant-sized heterotopic tumours (~250 mm3) and orthotopic rectal tumours, displaying their potential as theranostic nanoplatforms for targeting rectal cancer.

SmoGSI: smoothed multiscale iterative geostatistical seismic inversion

Iterative geostatistical seismic inversion is a vital technique for estimating subsurface properties. However, a conventional single-scale strategy faces challenges in preserving large-scale geological features due to the limited restoration of the type of data template, and conventional multiscale strategies face the challenge in that it is easy to lose the large-scale structure that was previously preserved. This paper introduces a novel smoothed multiscale strategy aimed at overcoming these limitations, which comprises two components: Simulated annealing at the coarsest scale and smooth conversation between two scale grids. This approach offers a smoother way to simultaneously retain large-scale and small-scale structures, improving the overall accuracy of the subsurface property estimations. To validate the effectiveness of our approach, we apply it to both synthetic and real examples. The results show that the simulated annealing strategy at the coarsest scale grid explores the prior space and finds the best large structures to avoid the generated models trapping in the local minimal. Meanwhile, the smooth conversation strategy between two scale grids helps us avoid the damage of the coarser structure. It can be explained that a large weight is assigned to the coarse structure at the beginning of the conversation of two grid scale, reducing the likelihood of the replacing proposed local small-scale geological patterns, which prone to be accepted in the conventional multiscale strategies. The combination of the two strategies used in the proposed smoothed multiscale strategy displays a significant improvement in subsurface property estimation accuracy compared to traditional multiscale strategies. This innovation can have far-reaching implications, benefiting a wide range of geophysical applications and contributing to more accurate and informed decision-making in geological and hydrogeological assessments.

Synergistic promotion strategy of “dual-site” and “dual-path” to enhance the C–C coupling between CO2 and HCHO driven by photoelectrocatalysis

Photoelectrocatalytic coupling CO2 and volatile organic compounds (VOCs) is a promising green strategy for the synergistic conversion of the two carbon-containing resources to C2 products. The catalytic efficiency is always at the mercy of chemical inertness of CO2 and the competitive hydrogen evolution of H2O. Herein, a modified g-C3N4/ZnAl-LDH Z-scheme heterojunction catalyst with dual reaction site was rationally designed and precisely constructed. The Faraday efficiency of ethanol reached 68.67% with a corresponding formation rate of 227.3 μmol g−1 h−1. As revealed by in-situ characterizations and density functional theory calculations, CO2 and HCHO were absorbed at Zn site and N site, respectively. Then, *CO generated from CO2 and HCHO was converted to *CH3O and *CHO on the dual-active-site heterojunction. The detailed reaction mechanism experiments indicated that C–C coupling only occurred between *CO and *CH3O in electrocatalysis process. Apart from the “*CO + *CH3O” path, another “*CO + *CHO” coupling path was also detected in photoelectrocatalytic process. The selectivity of ethanol was significantly enhanced due to the synthesis of dual-site catalyst and the dual-path coupling path between CO2 and HCHO simultaneously driven by light and electricity.

Octopus[5]arene from Pagoda[5]arene by Macrocycle-to-Macrocycle Conversion.

Macrocycle-to-macrocycle conversion is an effective strategy to construct new macrocyclic arenes with specific structures. Herein, a new class of chiral macrocyclic arene, namely, octopus[5]arenes (Oc5s), cannot be synthesized by the direct approach from the corresponding chiral monomers but can be successfully achieved by a macrocycle-to-macrocycle conversion strategy utilizing racemic pagoda[5]arenes as the starting materials. It was found that enantiomeric Oc5s showed fixed conformations and stable chiral structures and exhibited significant chiral recognition toward chiral diamines.

Electrocatalytic Upgrading of Biomass-Derived Compounds for Biofuel Production

Biomass fast pyrolysis liquid (also known as bio-oil) is considered to be one of the most promising renewable carbon feedstocks. However, fresh pyrolyzed bio-oil is acidic and corrosive and contains large amounts of carbonyl and phenolic compounds produced by polymerization under acidic conditions. This work primarily utilizes an electrochemical conversion strategy using only earth-abundant metal catalysts to achieve the carbonyl hydrogenation process. The results show that upgrading this process produces biofuels with greater stability and higher specific energy. In addition to analyzing the chemical implications of this conversion strategy, this work will also discuss why electrocatalytic conversion is a promising technology path for biofuels and fine chemicals. Reference Huang, S., Lam, C. H.* et al. (2022). "The Structural Phase Effect of MoS2 in Controlling the Reaction Selectivity between Electrocatalytic Hydrogenation and Dimerization of Furfural." ACS Catalysis 12(18): 11340-11354.Huang, S., Lam, C. H.* et al. (2022). "MoS2-Catalyzed Selective Electrocatalytic Hydrogenation of Aromatic Aldehydes in an Aqueous Environment." Green Chemistry.Tu, Q., Lam, C. H.* et al. (2021). "Electrocatalysis for Chemical and Fuel Production: Investigating Climate Change Mitigation Potential and Economic Feasibility." Environmental Science & Technology 55(5): 3240-3249.Garedew, M., Lam, C. H.* et al. (2020). "Greener Routes to Biomass Waste Valorization: Lignin Transformation Through Electrocatalysis for Renewable Chemicals and Fuels Production." ChemSusChem 13(17): 4214-4237. Lam, C. H., et al. (2017). "Towards sustainable hydrocarbon fuels with biomass fast pyrolysis oil and electrocatalytic upgrading." Sustainable Energy & Fuels 1(2): 258-266. Figure 1

Structure–Activity–Stability Relationship of Ru-Ir-Ti Electrocatalysts for the Oxygen Evolution Reaction

Environmentally friendly strategies for energy conversion and storage are urgently needed to account for natural intensity variations of power generation by renewables and to ensure a stable electrical grid. Green hydrogen, produced by water electrolysis, can be considered as one of the most promising energy carriers since it can balance the energy demand in multiple energy sectors. Proton exchange membrane water electrolyzers (PEMWE) are state of the art devices for on-site hydrogen production. Still, their upscaling is challenged by the corrosive acidic environment and sluggish anodic oxygen evolution reaction (OER), which demand using noble metal based catalysts [1, 2]. Currently, Ir-based oxides are employed as OER catalysts in commercial PEMWE as they provide the best balance between activity and stability. Yet, the scarcity and high market price of Ir lead to poor cost-benefit factors. In the last years, Ir-Ru mixed oxides have attracted significant attention of the community due to their improved electrocatalytic activity [2, 3]. However, Ru degradation during the OER becomes challenging in conditions of long-term operation of the electrolyzer. Therefore, balancing stability and activity towards the OER at reduced Ir loading remains a significant challenge in PEMWE.Here, we examine the effect of low additions of Ti (1 to 6 at. %) on the catalytic activity and stability of Ru-Ir alloys towards the OER [4]. The catalysts are synthesized as ternary Ru-Ir-Ti thin film material libraries with Ir contents below 50 at. %. After the high-throughput screening of these libraries for desired electrocatalytic properties by online inductively coupled plasma mass spectrometry (ICP-MS), the most promising alloy compositions are selected and tested in conditions of long-term electrolysis (Figure 1). The observed activity-stability trends are correlated with the electronic structure of the Ru-Ir-Ti catalysts derived from X-ray photoelectron (XPS) and X-ray absorption spectroscopies (XAS). Furthermore, the structural changes in the near-surface regions of these catalysts induced by the OER, are investigated with the aid of atom probe tomography (APT). Our data reveal formation of Ir-Ru hydrous oxide layers in the course of the OER, providing high catalytic activity, while Ti additions promote stabilization of these reactive oxides in the near surface region. Our multidisciplinary approach of combining advanced electrochemical, spectroscopic and atomic-scale characterization methods provides insights on structure-function relationships in electrocatalysis, guiding the rational design of active and stable electrocatalysts.[1.] Carmo, M., et al., A comprehensive review on PEM water electrolysis. International journal of hydrogen energy, 2013. 38(12): p. 4901-4934.[2.] Kasian, O., et al., On the Origin of the Improved Ruthenium Stability in RuO2-IrO2 Mixed Oxides. Journal of the Electrochemical Society, 2016. 163(11): p. F3099-F3104.[3.] Saveleva, V.A., et al., Uncovering the stabilization mechanism in bimetallic ruthenium–iridium anodes for proton exchange membrane electrolyzers. The journal of physical chemistry letters, 2016. 7(16): p. 3240-3245.[4.] Lahn, L., et al. Low Ti Additions to Stabilize Ru‐Ir Electrocatalysts for the Oxygen Evolution Reaction. ChemElectroChem, 2023, e202300399. DOI: https://doi.org/10.1002/celc.202300399. Figure 1

Ag/Nico LDH Heterogeneous Structure for Efficient Alkaline Oxygen Evolution

Hydrogen is regarded as an ideal energy carrier owing to the highest energy density, presenting the possibility of substituting for traditional fossil fuels. Nowadays, water splitting is significant in producing large-scale hydrogen. However, the sluggish reaction kinetics during anodic OER, caused by the four-electron transfer, has hindered this energy conversion strategy. Although IrO2 and RuO2 are currently the representative OER electrocatalysts, their high cost and unsatisfactory performance limit their commercial application.Numerous electrocatalysts, including oxides, hydroxides, high-entropy alloy, metal organic frameworks, and their hybrids, have been developed to address this issue. Among them, layered double hydroxides (LDH) have demonstrated outstanding performance due to their highly adjustable structure, powerful host-guest interaction, and single-atomic-like active sites. NiCo LDH has attracted significant attention because of its appropriate atomic and electronic structure, intrinsic active sites and defects, compared with single-type Ni-based or Co-based catalysts. However, to meet the requirements of industrial production, a simple and scalable method to synthesize electrocatalysts with favorable OER activity and stability is imperative.We propose a facile and scalable strategy to synthesize Ag-decorated NiCo LDH (Ag/NiCo LDH) by electrodeposition and subsequent spontaneous redox reaction. A spontaneous redox reaction driven by the difference in standard redox potential of reactants can be applied to prepare heterogeneous catalysts in consequence of the facile process, tight combination between substrate and decorated materials, and no supplementary energy input. Silver metal, with its appropriate standard redox potential, good conductivity, and low cost compared to Iridium and Ruthenium, serves as a suitable decorated material. This strategy provides several advantages, for example, Ⅰ) optimizing the electronic structure of Ni and Co by the charge transfer from Ni, Co to Ag; Ⅱ) exposing more active surface area because of the heterogeneous structure, Ⅲ) improving the charge transfer capacity owing to the excellent conductivity of Ag nanoparticles, Ⅳ) increasing the stability of NiCo LDH due to the tight combination of Ag and NiCo LDH, Ⅴ) lowering the catalysts' price compared with Iridium and Ruthenium.The synthesized Ag/NiCo LDH exhibits enhanced OER performance in 1M KOH electrolyte, achieving an overpotential of 440 mV at a current density of 1000 mA cm-2 geo, surpassing that of NiCo LDH (722 mV at 1000 mA cm-2 geo). Surprisingly, Ag/NiCo LDH demonstrates exceptional durability, lasting over 425 h at 1000 mA cm-2 geo, an improvement of nearly eight-fold compared to NiCo LDH (50 h). This study provides a promising approach for developing efficient and stable electrocatalysts for alkaline oxygen evolution.

Topic maintenance in non-fluent aphasia conversation

Background: Studies on communication partner training programs for persons with aphasia reveal improvements in the conversation partners’ communication skills. This article explores the strategies for topic maintenance developed by the conversational partners of three people with non-fluent aphasia before and after an intervention on conversational strategies. Method: We used conversation analysis to examine video-recorded samples of everyday conversations (pre- and post-treatment and follow-up) between three couples. The assessment for topic management was performed with Conversation Analysis Profile for People with Aphasia (CAPPA). The intervention was conducted over a period of five weeks. The partners were trained to use strategies for better topic maintenance (multiple-choice, multimodality, and message verification). At six weeks post-therapy, a third recording was made. Results: After the intervention, changes in topic maintenance were observed. The use of strategies is related to the pre-existing context and the presence of visual support. Discussion/Conclusion: Individuals with non-fluent aphasia and their conversation partners engage in multimodal conversations and benefit from the use of strategies to overcome barriers to understanding, leading them to maintain a conversational topic.

Upgraded cellulose and xylan digestions for synergistic enhancements of biomass enzymatic saccharification and bioethanol conversion using engineered Trichoderma reesei strains overproducing mushroom LeGH7 enzyme

Crop straws provide enormous lignocellulose resources transformable for sustainable biofuels and valuable bioproducts. However, lignocellulose recalcitrance basically restricts essential biomass enzymatic saccharification at large scale. In this study, the mushroom-derived cellobiohydrolase (LeGH7) was introduced into Trichoderma reesei (Rut-C30) to generate two desirable strains, namely GH7–5 and GH7–6. Compared to the Rut-C30 strain, both engineered strains exhibited significantly enhanced enzymatic activities, with β-glucosidases, endocellulases, cellobiohydrolases, and xylanase activities increasing by 113 %, 140 %, 241 %, and 196 %, respectively. By performing steam explosion and mild alkali pretreatments with mature straws of five bioenergy crops, diverse lignocellulose substrates were effectively digested by the crude enzymes secreted from the engineered strains, leading to the high-yield hexoses released for bioethanol production. Notably, the LeGH7 enzyme purified from engineered strain enabled to act as multiple cellulases and xylanase at higher activities, interpreting how synergistic enhancement of enzymatic saccharification was achieved for distinct lignocellulose substrates in major bioenergy crops. Therefore, this study has identified a novel enzyme that is active for simultaneous hydrolyses of cellulose and xylan, providing an applicable strategy for high biomass enzymatic saccharification and bioethanol conversion in bioenergy crops.

Analysis of Rice Fields Conversion to Improve Control Strategies: A SWOT Framework

Rice fields are the leading supplier of rice in Indonesia. The conversion of rice fields is a severe problem that needs to be addressed to support food security. This study aims to formulate a strategy to control the conversion of rice fields in Pematangsiantar City. We conducted a comprehensive SWOT analysis, identifying the strengths, weaknesses, opportunities, and threats to control rice field conversion. This analysis was based on focus group discussions and in-depth interviews with 24 key respondents. Based on the evaluation matrix of internal and external factors and the strategy matrix, the strategies to control rice field conversion are aggressive (SO strategy), adaptive (WO strategies), and competitive (ST strategies). The main strategies are regulatory consistency, incentive, and disincentive systems, preparation of LP2B Perda, consistency in issuing non-agricultural sector permits, and institutional capacity building of rice farmers. This research is the latest comprehensive study in formulating control strategies for rice field conversion in Pematangsiantar City. The contribution is a strategy that can be used as an action program to control the conversion of rice fields. Implementing the strategy requires technical and political will from all stakeholders, especially local government, legislators, and farmers.

Conversion of farmland to forest or grassland improves soil carbon, nitrogen, and ecosystem multi-functionality in a subtropical karst region of southwest China

The conversion of farmland to forest in China has been recognized for its positive impact on above-ground vegetation and carbon sequestration. However, the impact on soil quality during land conversion, particularly in vulnerable karst areas, has received less attention. In this study conducted in a karst area of southwest China, eight different farmland conversion strategies were investigated to assess improvements in surface soil carbon, nitrogen, and ecosystem multi-functionality (EMF). Our results showed that farmland converted to afforestation areas or farmland that was abandoned contained higher amounts of carbon (total, organic, active) and ammonium nitrogen (NH4+-N) in the soil compared to farmland converted to grassland or maize crop. Soluble organic carbon levels were higher in afforestation and grassland areas compared to maize crop controls. By contrast, soil from grassland and abandoned land exhibited higher levels of nitrate nitrogen (NO3--N) compared to afforestation land or maize crop controls. There were no differences in NH4+-N content between any condition, except for afforestation land that specifically contained the Zenia insignis plant species. Afforestation land consistently exhibited higher EMF values than grassland. Pearson correlation analysis revealed positive relationships between soil indices and EMF scores, except for NO3--N.Random forest analysis explained 95% of the variation in soil EMF and identified specific soil factors: total carbon, organic carbon, active labile organic carbon, total nitrogen, and ammonium nitrogen, as the main drivers of soil multi-functionality. Our studies show how various reforestation strategies can enhance soil nutrient sequestration and improve soil multi-functionality of farmland in the karst areas.These findings provide insight into sustainable soil management practices for converting farmland into natural areas.