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【Objective】 Organic fertilizers have been increasingly used as a substitute to reduce the detrimental impact of chemical fertilizers in China. In this paper, we studied the impact of its combination with drip irrigation water temperature on honey jujube growth and yield. 【Method】 The experiment was conducted in a field at Tuha Basin, where 10% to 90% of the chemical fertilizers was replaced by organic fertilizer. The control was without organic fertilizer substitution. For each fertilization, there were two irrigation water temperatures: conventional water temperature (13±1)℃ (T1) and warmed water temperature (21±1)℃ (T2). In each treatment, we measured water consumption, yield and water use efficiency of the jujube. 【Result】 When fertilization was the same, T2 reduced water content in the 0~100 cm soil layer and increased water consumption. Compared with T1, T2 increased yield and water use efficiency of the jujube by 7.15% and 5.10%, respectively. When the irrigation water temperature was the same, substitution of chemical fertilizer with organic fertilizer led to an increase in soil water content and water consumption. As a result, it increased the yield and water use efficiency of the jujube. However, when the substitution rate exceeded 50%, there was a decline in yield and water use efficiency. Specifically, when the substitution was 50%, T2 increased the yield and water use efficiency of the jujube by 10.10% and 6.95%, respectively, compared to T1. 【Conclusion】 Multivariate regression analysis suggested that under conventional irrigation water temperature, substituting 50.00%~55.64% of chemical fertilizer by organic fertilizer is optimal to improve yield and water use efficiency of the jujube, while when increasing the water temperature to 20 ℃, substituting 41.01%~49.83% of chemical fertilizer works the best for the jujube.

Optical anisotropic (e.g., birefringent) crystals can manipulate the polarization of light and thus are widely applied in modern optical fields. Common birefringent crystals are almost exclusively limited to inorganic oxides with small birefringence. Here, a new 1D hybrid halide perovskite PZPbCl3 (PZ = phenazine) is reported, which consists of perfectly parallel Pb–Cl chains and PZ cations. Remarkably, polarized optical observations show that even a PZPbCl3 crystal with micrometer thickness can modulate the polarized light efficiently. Furthermore, PZPbCl3 exhibits exceptional birefringence up to 0.65@546 nm, which is significantly larger than that of commercial oxide crystals. According to first‐principles calculations and polarizability anisotropy analyses, it is found that this birefringence is mainly ascribed to the linear polymerization of π‐conjugated rings in PZ cations. Due to the rich physical properties and structural diversity of hybrid perovskites, it is believed that the introduction of excellent birefringence into the hybrid perovskites will bring unprecedented opportunities to the future explorations of polarization‐dependent functional materials. [ABSTRACT FROM AUTHOR]

It is urgent to engineer an advanced electrocatalyst toward the oxygen evolution reaction for water electrolysis, and interface engineering is an effective method to boost the catalytic activity. Here we report Ag modified Co–phytic acid (Co-PA-Ag) with a hollow nanoprism structure for the OER. Co-PA is prepared by etching a Co precursor with phytic acid, and a spontaneous redox reaction is used to load Ag nanoparticles. The close contact between Co-PA and Ag modifies the electronic structure of Co-PA-Ag, which greatly improves its catalytic activity. The Co-PA-Ag only needs an overpotential of 270 mV at 10 mA cm–2, as well as long-term durability for 35 h. In addition, an electrolyzer featuring a Co-PA-Ag anode and Pt/C cathode exhibits rapid water splitting capacity with 100% Faraday efficiency, demonstrating its practical application. [ABSTRACT FROM AUTHOR]

Finding a deep-ultraviolet (deep-UV, λ < 200 nm) nonlinear optical (NLO) crystal is vital to a number of advanced optical technologies, yet it remains a great challenge. Herein, we report a deep-UV NLO crystal, K2B3O3F4(OH) (KBOFH), composed of π-conjugated confined groups. It exhibits a relatively large birefringence of 0.054@550 nm and a wide transparency window with an absorption edge below 200 nm. Theoretical calculations reveal that the observed optical properties of KBOFH originate from the confined π-conjugated [B3O3F4(OH)] unit, in which the π-conjugated interactions are decoupled by the tetrahedral non-π-conjugated [BO2F2] unit. This work provides an opportunity to design deep-UV NLO crystals containing π-conjugated confined groups. [ABSTRACT FROM AUTHOR]

Birefringent crystals as an important optical anisotropic material play a crucial role in modulating the polarization state of light. To date, most birefringent crystals are purely inorganic compounds with small birefringence. Developing large birefringent crystals remains a great challenge primarily because of the absence of tunable anisotropic structural units for inorganic materials. Herein, a hydrogen‐bonding self‐assembly strategy is reported to construct a robust hydrogen‐bonded organic framework (HOF, namely m‐H3L) birefringent crystal, which consists of π‐conjugated benzene rings and tetrahedral phosphonate groups interconnected via multiple H‐bonding interactions. Interestingly, the birefringence is as large as ∆n = 0.17@550 nm and catches up with those of commercial birefringent crystals. A combination of theoretical calculation and single‐crystal structural analyses reveals that the H‐bonding interactions control the dihedral angle of π‐conjugated benzene rings and the smaller the dihedral angle, the greater the birefringence. This discovery opens the door for the tunable HOFs to be used as a promising new class of birefringence materials. [ABSTRACT FROM AUTHOR]

The research work presents a novel voxel-type soft amphibious robot based on an assembly of origami flexiballs. The geometric and elastic constitutive models of the origami flexiball are theoretically established to elucidate its intricate deformation mechanism. Especially, the zero-energy storage phenomenon and the quasi-zero-stiffness characteristic are revealed to prove that the origami flexiball is suitable for serving as soft robotic components. As a proof of concept, fourteen origami flexiballs are interconnected to form a quadruped robot capable of walking or crawling in both underwater and terrestrial environments, including flat surfaces and sandy terrain. Its adaptability across multiple environments is enhanced by the origami polyhedra-inspired hollow structure, which naturally adjusts to underwater conditions such as hydrostatic pressure and currents, improving stability and performance. Other advantages of the voxel-type soft amphibious quadruped robot include its ease of manufacture using 3D printing with accessible soft elastic materials, ensuring rapid and cost-effective fabrication. We anticipate its potentially versatile applications, including underwater pipeline inspections, offshore maintenance, seabed exploration, ecological monitoring, and marine sample collection. By leveraging metamaterial features embodied in the origami polyhedra, the presented voxel-type soft robot exemplifies an innovative approach to achieving complex functionalities in soft robotics. [ABSTRACT FROM AUTHOR]

The outbreak of the coronavirus (COVID-19) pandemic has forced chemistry teaching from traditional classrooms to online courses worldwide. Herein, we will share some experiences of our online teaching of inorganic chemistry. First, we investigated various teaching platforms and adjusted the online teaching approaches for helping students to be more comfortable with online teaching. During the online class, attention was paid specifically to making the teaching process more topic-focused. This also prompted teachers to interact with students and give feedback in a timely manner. With the student-centered strategy and advanced network technology, we encouraged students to consult literature reports to better digest what they have learned in class and expand their knowledge, thus leading to higher teaching quality and promoting the cultivation of their talents. The overall processes are evaluated by examination, and finally, key points after one-semester online teaching are summarized to further improve future teaching quality. This work provides some rational guidelines toward high-quality online teaching for teachers and could readily expand to courses other than inorganic chemistry.