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A dual-template method was adopted to prepare hierarchical ZSM-5 zeolite and used for catalytic cracking of n-pentane to produce light olefins. Through regulation of the content of tetrapropylammonium hydroxide (TPAOH) and tetrabutylphosphonium hydroxide (TBPOH), ZSM-5 zeolites with tuneable proportions of micropores to mesopores are hydrothermally synthesized. In cracking reactions, mesopores provide spatial diffusion which enhances the conversion of reactants, and micropores confirm the cracking depth of the intermediate products. With TPAOH/TBPOH of 20/1 (molar ratio), the prepared catalyst (SP-1T) gives a yield of light olefins (ethylene and propylene) up to 48.2 wt% at 600 °C. The hierarchy factors (HFs) calculated from the textural properties show a positive correlation with TOFs based on the reactant conversion, but not with the yield of olefins. Moreover, the deep secondary reaction is inhibited over the SP-1T catalyst, thus leading to excellent catalytic stability.

Photodynamic therapy (PDT) has been considered an effective treatment for various types of cancers. However, hypoxic microenvironment within the solid tumor is averse to oxygen-involved PDT, resulting in low therapeutic efficacy. This Preview highlights a recent study regarding a synergistic therapy that combines PDT and chemotherapy, in which hypoxic solid tumor diagnosis imaging and therapy can be achieved.

Shale reservoirs, characterized by their relatively low permeability and porosity, often employ hydraulic fracturing techniques to increase production during development. However, conventional large-scale hydraulic fracturing encounters challenges such as excessive water consumption, low flowback rates, and environmental concerns. Given the increasing scarcity of water resources and increased emphasis on sustainability environmental sustainability, hydraulic fracturing no longer meets the requirements for green and environmentally friendly extraction. The utilization of supercritical CO2fracturing technology emerges as a promising alternative, offering advantages such as reduced water usage and minimized environmental impact. Additionally, this technology allows for the sequestration of CO2underground, presenting an integrated approach to CO2geological storage and oil-gas extraction. Supercritical CO2possesses many unique physical and chemical properties. However, the micro-mechanisms governing its interaction with rock during fracturing, along with the mechanisms and propagation characteristics of fracture initiation, necessitate further in-depth investigation. This study aims to explore the development mechanisms of supercritical CO2fractures under the influence of single factor variables and natural fractures of different sizes (2 m, 4 m, and 6 m). To explore the interaction mechanisms between natural fractures and supercritical CO2fractures, single factor variable control experiments were conducted with natural fracture angles of 30 °, 45 °, and 60 °, and in-situ stress deviations of 3, 5, 7, and 9 MPa. Our research delves into the impact of natural fracture inclination angle, in-situ stress deviation, and natural fracture size on supercritical CO2fractures development. This comprehensive exploration unveils the intricate interaction mechanisms between natural fractures of different sizes and supercritical CO2fractures. Various control chart were studied, considering different natural fracture under diverse ground stresses and inclinations. The findings of this study bear theoretical significance and engineering application for enhancing efficiency in shale gas production.

Catalytic cracking of JP-10 is an important technology to improve its cooling capacity (or heat sink). Two HZSM-5 zeolite nanosheets with Si/Al molar ratios of 25 and 50 (ZNS-25 and ZNS-50) and thicknesses of about 2.0 nm were synthesized. The catalytic cracking of JP-10 (at 500 °C with a weight hourly space velocity = 22.56 h–1) over ZNS-25 gave a conversion of 45.33%, which is 77% higher than that obtained over a conventional HZSM-5 catalyst (CZ-25, 25.54%), and the deactivation rate was relatively low (two-thirds that of CZ-25). Characterization of the catalysts using ammonia temperature-programmed desorption measurements and Fourier transform infrared spectroscopy indicated that the better catalytic performance may be attributed to more Brønsted acid sites on the external surface, which is favorable for the larger molecules (like JP-10), and higher accessibility of acid sites in the micropores of HZSM-5 nanosheets due to the shorter diffusion path (less than 2.0 nm). The enhanced diffusion of JP-10 over HZSM-5 nanosheets also leads to high olefin yields, and better coking tolerance through prevention of secondary reactions.

A series of magnetic porous Fe–C materials were prepared by one-step pyrolyzation of ethylenediaminetetraacetic acid sodium iron(III) at 500°C–800°C and then employed as adsorbents for sulfamethoxazole (SMX) adsorption. The one prepared at 700°C (Fe–C-700) was selected as the optimum one with an adsorption amount of 82.3 mg g–1at pH 5.0 and 30°C. This was mainly ascribed to its higher surface area which offered more space for hydrophobic and electron donor–acceptor interactions between SMX and its surface. The adsorption kinetics was analyzed with three models. With the increase of concentration, the k1value decreased from 0.383 to 0.329 min–1, and the k2value decreased from 0.0292 to 0.0101 g mg–1min–1. The thermodynamic analysis showed that SMX adsorption on Fe–C-700 was a spontaneous exothermic entropy-decreasing process. The effects of adsorbent dosage, pH, metal ions and humic acid on SMX adsorption were also investigated. The spent Fe–C-700 could be easily separated and recycled after adsorption due to its magnetic feature.

Direct synthesis of hydrogen peroxide (DSHP) was studied over Pd loaded on HZSM-5 nanosheets (Pd/ZN). Pd nanoparticles with average size of ca.4.3 nm were introduced into the adjacent nanosheet layers (thickness of ca.2.9 nm) by impregnation method. Pd/ZN with theoretical Si/Al molar ratio of 25 showed the highest selectivity for H2O2among the prepared catalysts, together with highest formation rate of H2O2(38.0 mmol·(g cat)−1·h−1), 1.9 times than that of Pd supported on conventional HZSM-5 zeolite (Pd/CZ-50). Better catalytic performance of nanosheet catalysts was attributed to the promoted Pd dispersion which promoted H2dissociation, more Brønsted acid sites and stronger metal-support interaction which inhibited the dissociation of OO bond in H2O2. The embedded structure sufficiently protected the Pd nanoparticles by space confinement which restrained the Pd leaching, leading to a better catalytic stability with 90% activity retained after 3 cycles, which was almost 3 times than that of Pd/CZ-50 (30.4% activity retained).

Triplet–triplet annihilation upconversion (TTA-UC) has great potential in many fields. However, a stable TTA-UC system with adjustable UC efficiency in non-deoxygenated water is still in urgent demand. Here, the first example of short peptide-tuned UC luminescence in water is reported. With only a small amount of peptides, UC chromophores can assemble into tetrahedral microrods with adjustable size and UC efficiency. Successful TTA-UC luminescence of these microrods in water is achieved due to the regular and dense organization of molecular upconversion chromophores tuned by peptides, which allows rapid triplet exciton migration, avoids aggregation-induced quenching and screens molecular oxygen to upconversion chromophores.

The combined effects of straw incorporation (SI) and polymer-coated urea (PCU) application on soil ammonia (NH3) and nitrous oxide (N2O) emissions from agricultural fields have not been comprehensively evaluated in Northwest China. We conducted a two-year field experiment to assess the effects of combining SI with either uncoated urea (U) or PCU on soil NH3emissions, N2O emissions, winter wheat yields, yield-scaled NH3(INH3), and yield-scaled N2O (IN2O). Five treatments were investigated, namely no nitrogen (N) fertilizer (N0), U application at 150 kg N ha-1(S0+U), U combined with straw (SI+U), PCU application at 150 kg N ha-1(S0+PCU), and PCU combined with straw (SI+PCU). The results showed that the NH3emissions increased by 20.98-34.35% following SI compared to straw removal, mainly due to increases in soil ammonium (NH4+-N) content and water-filled pore space (WFPS). SI resulted in higher N2O emissions than under the S0scenario by 13.31-49.23% due to increases in soil inorganic N (SIN) contents, WFPS, and soil microbial biomass. In contrast, the PCU application reduced the SIN contents compared to the U application, reducing the NH3and N2O emissions by 45.99-58.07% and 18.08-53.04%, respectively. Moreover, no significant positive effects of the SI or PCU applications on the winter wheat yield were observed. The lowest INH3and IN2Ovalues were observed under the S0+PCU and SI+PCU treatments. Our results suggest that single PCU applications and their combination with straw are the optimal agricultural strategies for mitigating gaseous N emissions and maintaining optimal winter wheat yields in Northwest China.

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•66.4% of patients with well controlled NMOSD had comorbid current pain.•28.7% of patients with well controlled NMOSD had comorbid neuropathic pain.•Depression correlated with neuropathic pain in NMOSD and was ignored.•More patients with neuropathic pain in NMOSD had initial spinal cord involvement.•Quality of life was severely affected in NMOSD patients with neuropathic pain.

Extraction–oxidation desulfurization (EODS) technology would be a potential industrial application for achieving ultralow-sulfur fuel oils. A combined extraction–oxidation system for dibenzothiophene removal from model fuel with H2O2as an oxidant, acetonitrile as an extractant, and Mo/γ-Al2O3as a catalyst was performed in a batch reactor. To study this complex heterogeneous system, the chemical reaction and mass transfer on each phase were individually assessed. Kinetics of the EODS system for dibenzothiophene in model fuel was developed, comprising the chemical kinetic mechanism and mass transfer effects. The kinetic parameters of the kinetic model, such as the kinetic constants and apparent activation energy, were determined. The EODS system in the experimental condition is determined by both the extraction process and catalytic oxidation reaction, because the terms involving the intrinsic resistance of the chemical reaction are no more important than mass transfer resistance.

Ordered meso-HZSM-5 zeolites with Al-MCM-41 shells were synthesized by a surfacant-directed encapsulating process. It was found that ordered meso-HZSM-5, which was used as a core, could be synthesized using a designed amphiphilic organosilane as a surfactant and that the mesopore size of the MCM-41 shell can be adjusted from 2.5–3 to 4.5–10 nm by changing the structures of alkyltrimethylammonium bromide and the trimethylbenzene amount. Catalytic cracking performances of supercritical n-dodecane (500 °C and 4 MPa) show that ordered meso-HZSM-5 zeolites with Al-MCM-41 shells of 4.5–10 nm exhibit a 28% higher catalytic activity and a 25% lower deactivation rate compared to the conventional HZSM-5 zeolites. With an increasing mesopore size of the MCM-41 shell, the acid sites accessibility increased gradually and, thus, led to enhanced catalytic activity and decreased secondary reaction ability. In addition, ordered hierarchical zeolites show a well connection of ordered mesopores between the core and shell, which could also lead to the enhanced acid site accessibility.

The three-dimensional loading capacitated vehicle routing problem is a strong NP-hard problem. Most existing algorithms for the problem are heuristic or meta-heuristic algorithms. In this paper, an exact algorithm is proposed for the problem. For solving the loading sub-problem, we use an effective method to generate possible points for loading items, which greatly reduce the search scope. Then we proposed an exact algorithm witch iteratively calls a branch-and-bound algorithm based on set partition. The validity of the proposed algorithm is examined by comparing the present results with those of published algorithms using the same data.

A priority-considering heuristic approach is proposed to solve the multiple container loading problem, i.e., the problem of packing a given set of three-dimensional rectangular items into multiple containers to make the maximum use of the container space. The items with large volume are usually difficult to make efficient use of the container space. These items are set higher priority over other items, and preferentially assigned into the containers. Within the proposed approach an algorithm is used for solving the single container loading problem under the constraint of priority. The proposed approach achieves excellent results for the test cases suggested by Ivancic et al. and Mohanty et al. with reasonable computing time.

A critical problem in robotic manufacturing is that the task of teaching robotics is rather time-consuming. This has become a serious problem in the present age of cost reduction. Collaboration with a company in the field has revealed that the root cause of this problem is that there is not a common knowledge base in this domain, which can serve as shared and reused knowledge. In robotic manufacturing, the skills and experiences of skilled workers are a form of tacit knowledge that is difficult to be acquired and transferred to other workers and robots. This paper proposes a knowledge-based system for sharing and reusing tacit knowledge in the robotic assembly domain. In this system, a modified EBL (Explanation-based Learning) method is proposed to generalize tacit knowledge from specific robotic programs made by skilled workers. A newly operational criterion is proposed for the generalized tacit knowledge, which demands that it should be expressed understandably by human workers and be reusable by robots to generate programs automatically.

Robots must be presently taught by human workers to execute given manufacturing tasks. The current problem is that the task of teaching robots is rather time-consuming, especially within the robotic assembly domain. This problem is caused by insufficient accumulation of human expertise that should be reused in this domain. Therefore, a knowledge-intensive method for acquiring human expertise is proposed in this paper. Our method is able to acquire human expertise in the robotic assembly domain by observing robot-teaching demonstrations of human experts. What distinguishes our method from others is that there are two modes of learning: 1. learning from an example directly given by human workers, and 2. learning expertise on error recovery by observing revisions made by human workers in handling execution errors that occur in reusing previously acquired knowledge. The acquired human expertise is required to be represented in a way that satisfies two requirements. The first one is operability so that the representation is easy to transform into robot programs (commands & parameters). The second one is understandability so that the representation is easy for human workers to understand the robot program. A specific robot assembly example is given to illustrate the proposed method.

The container loading problem, a real hard problem, is usually difficult to obtain even a suboptimal solution because of not only multiple complicated restrictions but also of multiple objectives. In this paper, a heuristic algorithm is proposed for solving the two-row pattern of the container loading problem in real-world. The algorithm is based on Drum-Buffer-Rope (DBR) presented in the Theory of Constraints (TOC) and the multiagent cooperative negotiation model. A particular attention is focused on improving the constrained agent by striving for the trade-off of restrictions and cooperative negotiations, so that the final solution can arrive its biggest profit.

The high degree of adaptability of ecological systems to environmental variations enables them to live and reproduce under their dynamic environment. In this paper, as an example of ecological systems, four kinds of fish school models with different properties are presented for investigating the adaptability to environmental variations. The property of each model is represented in its parameters estimated from a water tank experiment data. Various simulations are carried out by using the respective models under an environment designed by setting an obstacle in the behavior space. The adaptive behavior is compared based on the simulation results. The relationship between their adaptability and system properties is discussed.

A fish school is considered as a typical example of autonomous decentralized system (ADS) or a self-organizing system existing in nature, because it often shows a high degree of coordinative behavior in the absence of a leader. A mathematical model was proposed in our earlier paper to describe the behavior of a homogeneous fish school which consists of individuals with almost the same character. In this paper, another model is proposed to describe the behavior of a heterogeneous fish school, in which there exist individuals with different characters. Since the behavior of a fish school varies with environmental variations, simulations are carried out by setting a box-shaped trap in a behavior space as an obstacle. The self-organization of the school and the variations of moving pattern with changing the quantity of information exchange among individuals are discussed.

Schematic diagram of regulating acid sites (Brønsted acid as an example) on the external surface of nanosheet HZSM-5 and possible reaction path of n-decane.