Gas Phase-Heat Absorption-Condensate Phase Stepwise Flame Retardant Strategy to Prepare Coal Tar Pitch-Based Porous Carbon for Supercapacitor.

Porous carbon is widely used in energy storage-conversion systems, and the question of how to explore an efficient strategy for preparation is very significant. Herein, the flame retardant capability of (NH4 )2 SO4 /Mg(OH)2 that contains gas phase-heat absorption-condensate phase components is assisted to carbonize coal tar pitch in air and obtain the porous carbon. The mechanism of stepwise inflaming retarding is systematically investigated. In the carbonization process in a muffle furnace, (NH4 )2 SO4 decomposes releasing gases at below 400 °C to act as the role of gas phase flame retardant. Mg(OH)2 starts to decompose at ≥ 400 °C, and it has the effect of heat absorption and condensed phase flame retardation (MgSO4 and MgO). What's more, the flame retardant also serves as an N, S source and template. The obtained porous carbon possesses an ultrahigh carbon yield of 56.9 wt.%, hierarchical pore structure, and multi-heteroatoms doping. It can still reach up to 244.7 F g-1 even loaded 20 mg of active material. In addition, the (NH4 )2 SO4 /agar gel electrolyte is synthesized, and the fabricated flexible ammonium ion capacitor exhibits a superior energy density of 40.8 Wh kg-1 . This work uncovers a new way to construct porous carbon, which is expected to synthesize more carbon materials using other carbon sources.

Optimizing nitrogen fertilizer for improved root growth, nitrogen utilization, and yield of cotton under mulched drip irrigation in southern Xinjiang, China.

The root system plays a crucial role in water and nutrient absorption, making it a significant factor affected by nitrogen (N) availability in the soil. However, the intricate dynamics and distribution patterns of cotton (Gossypium hirsutum L.) root density and N nutrient under varying N supplies in Southern Xinjiang, China, have not been thoroughly understood. A two-year experiment (2021 and 2022) was conducted to determine the effects of five N rates (0, 150, 225, 300, and 450 kg N ha-1) on the root system, shoot growth, N uptake and distribution, and cotton yield. Compared to the N0 treatment (0 kg N ha-1), the application of N fertilizer at a rate of 300 kg N ha-1 resulted in consistent and higher seed cotton yields of 5875 kg ha-1 and 6815 kg ha-1 in 2021 and 2022, respectively. This N fertilization also led to a significant improvement in dry matter weight and N uptake by 32.4% and 53.7%, respectively. Furthermore, applying N fertilizer at a rate of 225 kg N ha-1 significantly increased root length density (RLD), root surface density (RSD), and root volume density (RVD) by 49.6-113.3%, 29.1-95.1%, and 42.2-64.4%, respectively, compared to the treatment without N fertilization (0 kg N ha-1). Notably, the roots in the 0-20 cm soil layers exhibited a stronger response to N fertilization compared to the roots distributed in the 20-40 cm soil layers. The root morphology parameters (RLD, RSD, and RVD) at specific soil depths (0-10 cm in the seedling stage, 10-25 cm in the bud stage, and 20-40 cm in the peak boll stage) were significantly associated with N uptake and seed cotton yield. Optimizing nitrogen fertilizer supply within the range of 225-300 kg N ha-1 can enhance root foraging, thereby promoting the interaction between roots and shoots and ultimately improving cotton production in arid areas.

[Research on the relevance of earthworms inducing soil Cd2+ absorbed by perennial ryegrass].

Through the method of simulating the heavy metal pollution in farmland, the graphite oven (GF-990) atomic absorption was used for analyzing the regulations of the earthworms inducing the soil Cd2+ absorbed by the perennial ryegrass. The result indicated: (1) under the circumstance of the soil Cd2+ density of 3-6 mg x kg(-1), the positive relevance appeared extremely remarkably that the contents of Cd2+ in underground portions of the perennial ryegrass relate to the earthworm quantity (r = 0.883 2-0.986 2), but in the portion above ground the positive relevance did not appear extremely remarkably (r = 0.345 5-0.325 4); And the negative relevance appeared remarkably that the contents of Cd2+ in the soil relate to the earthworm quantity (r = -0.588 7(-) -0.678 4). (2) Under the conditions of isometric number of earthworms, the more the density of Cd2+ in the soil, the more the increase of Cd2+ in both portions under and above ground of perennial ryegrass. (3) Under the same soil environment, the negative relevance appeared that the number of earthworms relates to the contents of Cd2+ in the earthworms (r = -0.982 0(-) -0.991 6).

[Comparative analysis of endogenous hormones between two species of Ammopiptanthus seedlings around germination and under Pb2+ stress].

The changes in three endogenous hormones, phytohormones gibberrelic acid (GA3), indoles-3-acid (IAA) and abscisic acid (ABA), were studied around germination and under tress of different density of Pb2+ between two species of Ammopiptanathus. It was found that (1) around germination, in Xinjiang Ammopiptanthus the rate IAA decreased 77.80%, and the rate of ABA decreased 98.90%; and in Mongolia Ammopiptanthus the rate of IAA decreased 75.80%, the rate of ABA decreased 66.20%, and the GA3 contents in both had no big change. (2) With the increase in Pb2+ concentration (20-1 500 mg x L(-1)), the IAA decreased significantly; and only under the high density (more than 1 000 mg x L(-1)) of Pb2+, the GA3 was affected by it; the ABA did not change regularly. So the three endogenous hormone levels of Mongolia Ammopiptanthus were higher than those of Xinjiang Ammopiptanthus. (3) the distributions of Pb2+ in Ammopiptanthus seedlings are the root > stems > leaves. (4) the stress of high concentration of Pb2+ damages irreversibly the leaf cells of Ammopiptanthus. This study can provide the basis of reference data for further research on the growth characteristics, resilience and the mechanism of specific broad-leaved evergreen shrubs-Ammopiptanthus in desertification area.

[Effects of nitrogen application level on photosynthate distribution of Korla fragrant pear trees]. / æ–½æ°®æ°´å¹³å¯¹åº“å°”å‹’é¦™æ¢¨å ‰åˆäº§ç‰©åˆ†é çš„å½±å“.

Using 13C pulsed labeling technique, we examined the biomass and carbon accumulation of different organs as well as the distribution characteristics of 13C assimilate of 6-year-old Korla fragrant pear trees under three nitrogen application levels, i.e., 150, 300, and 450 kg N·hm-2 (marked as N1, N2, and N3, respectively). Results showed that the biomass, carbon accumulation, 13C fixation and leaf assimilation capacity of the whole pear tree increased while root to shoot ratio decreased with increasing nitrogen application. Both biomass and carbon accumulation amount of reproductive organs (i.e., fruits) were the highest under N2 treatment. The 13C content and distribution rate of each organ changed dynamically along with increasing nitrogen application. At the new shoot growing stage, leaves and roots had stronger competitive abilities for photosynthate, with 13C distribution rates being the highest under N1 treatment. During fruit swelling and mature stages, leaves and fruits were more competitive, with 13C content and distribution rate in leaves being the highest under N3 treatment and those in fruits being the highest under N2 treatment. According to the absorption and distribution characteristics of carbon assimilate across organs under the three nitrogen application levels, the optimal nitrogen application level for achieving high fruit yield in the 6-year-old Korla fragrant pear tree orchard is recommended as 300 kg·hm-2 .

[Effects of phosphorus fertilization on biomass accumulation and phosphorus use efficiency of trellis-cultivated melon].

A field experiment applying six rates of P fertilizer (P2O5, 0, 150, 225, 300, 375 and 450 kg . hm-2, respectively) was conducted to investigate the effects of P fertilization on dry matter accumulation (DMA), P uptake and accumulation (PUA) and P use efficiency (PUE) of trellis-cultivated melon. Results showed that, P application increased DMA and PUA, for 150 and 225 kg P2O5 . hm-2 treatments, being 19.9% and 26.3%, 23.0% and 26.3% higher than that in no P fertilizer treatment at fruiting stage. With plant growth, DMA and PUA of different organs and the whole plant gradually increased. DMA and PUA were mainly distributed in the leaves during the early stage of the growth and in the fruit during the latter stage. P application decreased the recovery efficiency of applied P (REP), agronomic efficiency of applied P (AEP) and partial factor productivity of applied P (PFP). At 150 kg . hm-2 P application rate, the maximum REP, AEP and PFP were 11.1%, 152.9 kg . kg-1 and 476.3 kg . kg-1, respectively. Compared with no P fertilizer treatment, melon yields of 150 and 225 kg P2O5 . hm2 treatments increased by 47.3% and 39.7%, respectively. In summary, the vining stage and fruit expanding stage were the key periods for P application in trellis-cultivated melon system. Based on synthesized economic yield and P fertilizer efficiency, the recommendation of P fertilizer for trellis-cultivated melon is 150-225 kg P2O5 . hm-2 under the climatic condition of the experimental area.