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As one of the emerging nanomaterials, boron nitride nanotubes (BNNTs) provide promising opportunities for diverse applications due to their unique properties, such as high thermal conductivity, immense inertness, and high-temperature durability, while the instability of BNNTs due to their high surface induces agglomerates susceptible to the loss of their advantages. Therefore, the proper functionalization of BNNTs is crucial to highlight their fundamental characteristics. Herein, a simplistic low-cost approach of BNNT surface modification through catechol-polyamine (CAPA) interfacial polymerization is postulated to improve its dispersibility on the polymeric matrix. The modified BNNT was assimilated as a filler additive with AlN/Al2O3 filling materials in a PDMS polymeric matrix to prepare a thermal interface material (TIM). The resulting composite exhibits a heightened isotropic thermal conductivity of 8.10 W/mK, which is a ~47.27% increase compared to pristine composite 5.50 W/mK, and this can be ascribed to the improved BNNT dispersion forming interconnected phonon pathways and the thermal interface resistance reduction due to its augmented compatibility with the polymeric matrix. Moreover, the fabricated composite manifests a fire resistance improvement of ~10% in LOI relative to the neat composite sample, which can be correlated to the thermal stability shift in the TGA and DTA data. An enhancement in thermal permanence is stipulated due to a melting point (Tm) shift of ∼38.5 °C upon the integration of BNNT-CAPA. This improvement can be associated with the good distribution and adhesion of BNNT-CAPA in the polymeric matrix, integrated with its inherent thermal stability, good charring capability, and free radical scavenging effect due to the presence of CAPA on its surface. This study offers new insights into BNNT utilization and its corresponding incorporation into the polymeric matrix, which provides a prospective direction in the preparation of multifunctional materials for electric devices. [ABSTRACT FROM AUTHOR]

Summary: Solar steam generation has proven to be a sustainable method to handle water shortage. Various materials for solar steam generation have been introduced in the past few years. However, the utilization of tedious and complicated synthesis to generate a photoactive layer is a matter of concern in the fabrication solar steam generation devices. Thus, improved methods toward cost‐effectiveness by exploring economical materials with simple manufacturing process are urgently and essentially needed. In this study, we first report on manufacturing hybrid membranes using commercially accessible materials, that is, cellulose paper and pencil graphite. The proposed method is to trace and coat a cellulose paper directly with a pencil without the use of solvents and chemicals, and it is possible to create an ecofriendly photoactive layer without a complicated process. The formed pencil graphite‐traced membranes were successfully utilized in solar steam generation and showed excellent steam generation rate of 4.32 kg/m2h which is almost 3.5 times more than that of pristine membrane at solar intensity of 3 Sun. The developed method could be widely utilized in the field of solar steam generation, since it is very facile and simple, and can be integrated to other commonly used materials for solar steam generation such as fabric and wood. In addition, on‐site production is possible, so it has a potential to be utilized in remote and resource‐limited areas for steam generation. [ABSTRACT FROM AUTHOR]

Herein, we report the solution‐based method for coating sulfur polymers on various substrate materials. First, sulfur polymers were synthesized by reacting elemental sulfur and 1,3‐diisopropenylbenzene and dissolved in various organic solvents to search for solvents with good solubility. Next, the trend in film thickness of sulfur‐polymer coating was systematically examined using the sulfur‐polymer solutions in dichlorobenzene (DCB) and various materials with different surface energy. The nanofibrillar film made of the poly(vinyl alcohol) and poly(acrylic acid) (PVA‐PAA) blend exhibited the most uniform/conformal deposition of sulfur polymer via dipping‐coating, indicating that the DCB solution is most suitable for the well‐controlled deposition of sulfur polymer on nanostructured materials with higher surface energy than 40 mN/m. Finally, the resultant sulfur polymer‐coated nanofibrillar film showed high mercury ion uptake capacity (26 mg/g with 50 ppm Hg solution) even with a small amount of sulfur‐based adsorbent (20 mg) loading on the film (40 mg). Our study suggests that the sulfur polymer solution can introduce the crucial properties of elemental sulfur on the surface of any conventional materials even with mechanical flexibility and nano/microscale structural complexity. [ABSTRACT FROM AUTHOR]

Field trial was initiated at Agriculture University New Developmental Farm, Agriculture University Peshawar-Pakistan during Kharif 2012 to study the weed management in maize through different control techniques. The experimental design was Randomized Complete Block (RCB) with three replications. The size of each individual plot was 5 × 3 m2. Azam variety at seed rate 28kg ha-1 was sown in the field with recommended rate nitrogen and phosphorus. The data were recorded on density of weed (m-2) before treatments application, density of weed (m-2) after treatments application, dry weed biomass (g), fresh weed biomass (g), maize plant height, number of cobs per plant, grains per cob, thousand grain weight, biological and grain yield (t ha-1). Results showed that lowest weed density (38.3 m-2) was recorded in black plastic mulch treatment. The highest plant height (199.0 cm) was observed in hand weeding twice treatment followed by Dual gold 960 EC and stomp 330 E treated units (196.0 cm each). The hand weeding twice produced highest grain yield (7.035 kg ha-1) which were statistical similar with Dual gold 960 EC (6.891kg ha-1), black plastic mulch (6.585 kg ha-1), hand weeding once (6.436 kg ha-1) and Stomp (5.966 kg ha-1); while, weedy check showed lowest grain yield of 3.892 kg ha-1. It can be concluded that mulching was superior over all other methods for controlling weed and maize crop performance over all other method. The findings may be applicable to other crops-that needs further research. [ABSTRACT FROM AUTHOR]

In the current research an efficient transformation system for sugarcane was established. Shoot tip of variety HSF-240, excised from a six months old field grown plants were used as explant. For transformation, Agrobacterium tumefaciens strain EHA101 with vector pIG121 Hm, harboring GUS, HPTII and NPTII genes were used. HPTII is a hygromycin resistant while NPTII is a kanamycin resistant gene. Effects of Acetosyringone, duration of co-cultivation and pre-selection, concentration of cefotaxime and hygromycin in medium on transformation efficiency were studied. High transformation efficiency and 60% GUS expression was observed when 50 μM acetosyringone was added in the co-cultivation medium. Among different durations of co-cultivation, 48 h produced high (40%) transient GUS positives with an absolute control of bacterial growth. For pre-selection, seven days gave a high transformation efficiency of 10%. Cefotaxime concentration of 1000 mg/L proved optimal for pre-selection of the explants with efficient control of bacterial growth. A high regeneration (31%; P < 0.01) of the transformants was observed at 50 mg/L hygromycin. Presence of GUS gene was confirmed by PCR analysis and only the transgenic plants contained the 430 bp fragment of GUS gene. The new protocol developed in this study could be used for the efficient transformation of sugarcane with desired gene to produce insect/pest resistant, drought tolerant and high yielding sugarcane varieties in future. [ABSTRACT FROM AUTHOR]

An experiment was conducted at Agricultural Research Station Ahmad Wala, Karak, Khyber Pakhtunkhawa-Pakistan, during rabi season 2006-07 for elaborating the effect of weeding methods on the yield and yield components of chickpea. The experimental design was Randomized Complete Block (RCB) with split plot arrangement. The experiment was replicated four times with the main plots including three varieties of chickpea whereas the subplots comprised of four treatments viz. hand weeding one time, hand weeding twice, Isoproturon 500 EW and a weedy check. The weedicide Isoproturon was applied @ 0.741 kg a.i. ha-1 as a post emergence. The data were recorded on number of weeds m-2, number of productive branches plant-1, number of pods plant-1, number of grains pod-1, 1000 grain weight (g), grain yield kg ha-1 and cost benefit ratio, Number of weeds m-2, number of productive branches plant-1, number of pods plant-1, number of grains pod-1, 1000 grains weight (g) and grains yield (kg ha-1) were significantly affected by different treatments. Maximum grain yield was produced by normal hand weeding twice treatment (1429.90 kg ha-1) and proved to be the best one, while lowest grain yield (777.95 kg ha-1) was recorded in weedicide application. Similarly maximum number of pods plant-1 (52.50), number of grains pod-1 (2.42), number of productive branches plant-1 (6.42), 1000 grain weight (235.58 g) and highest grain yield (1429.90 kg ha-1) were recorded in normal hand weeding twice treatment. The Cost: benefit analysis revealed the highest cost: benefit ratio of 1:1:9 in the hand weeding twice. Thus, hand weeding of chickpea twice is recommended for the chickpea growers of Karak, Khyber Pakhtunkhawa-Pakistan. [ABSTRACT FROM AUTHOR]

The application potential of nanocellulose has been previously hindered by the costly and slow drying methods that this material requires, including freeze/supercritical drying process. The main issue for nanocellulose commercialization is how effectively and rapidly its high water contents (90-99%) can be removed, all of which raise its transportation and processing costs. Oven-drying is the fastest, most economical, and most scalable method for dehydrating nanocellulose, but causes strong interfibrillar aggregation and leads to poor aqueous re-dispersion. Here, we report that the problems of nanocellulose oven-drying are comprehensively overcome by adding tert-butanol (t-BuOH) to the nanocellulose solution at >90%. In a lab-scale comparison, the t-BuOH-mediated oven-drying of aqueous nanocellulose showed lower drying times by a factor of 2-12 compared to water only oven-drying and freeze drying of the same material. The dispersibility of this dried nanocellulose is as high as the never-dried material in terms of particle size, light transmittance, and sedimentation. t-BuOH reduces interfibrillar shrinkage due to the lower surface tension of t-BuOH compared to water, and a remaining t-BuOH/water mixture decreases interfibrillar adhesion and contact.This paper suggests a strategy to improve the aqueous re-dispersibility of oven-dried nanocellulose, and to accelerate oven-drying rate. [ABSTRACT FROM AUTHOR]

Over the past few years, the ability to efficiently increase boron nitride nanotube (BNNT) production has opened up ample research possibilities. BNNT has garnered significant attention for diversifying its industrial applications. However, the problem of poor processability resulting from agglomeration and uneven distribution has emerged as a major challenge to integrating BNNT into the polymer matrix for composite material formation. Utilizing noncovalently attached molecules with various reactive sites can be a logical method to enhance the compatibility of BNNT with different polymers. The present study explored a simple approach to protruding BNNT onto the surface of Al 2 O 3 through tannic acid (TA)-assisted generation of alkyl chains (octadecylamine, ODA) to fabricate Al 2 O 3 @ODA-BNNT. The subsequent compounding of Al 2 O 3 @ODA-BNNT with epoxy polymer generates interconnected thermal conduction pathways, thereby improving the thermal conduction and mechanical performance of the composites. The current research approach allows for the even distribution of BNNT throughout the polymer matrix, as demonstrated by optical characterization, mechanical performance analysis, and isotropic thermal conductivity analysis. The fabricated epoxy composite by incorporating a 2 wt % (BNNT = 1.3 wt % and ODA = 0.7 wt %) ODA-BNNT exhibited 5.117 W/mK thermal conductivity and 7.43 MPa mechanical stress. Thermal conductivity improved by 2528, 76.56, and 54.7%, while mechanical stress enhanced by 270, 221, and 34% compared to neat polymers without BNNT and virgin BNNT epoxy composites, respectively., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)