Shared memory parallel computing procedures for nonlinear dynamic analysis of super high rise buildings

The proposed parallel state transformation procedures (PSTP) of fiber beam-column elements and multi-layered shell elements, combined with the parallel factorization of Jacobian (PF), are incorporated into a finite element program. In PSTP, elements are classified into different levels of workload prior to state determination in order to balance workload among different threads. In PF, the multi-threaded version of OpenBLAS is adopted to compute super-nodes. A case study on four super high-rise buildings, i.e. S1~S4, has demonstrated that the combination of PSTP and PF does not have any observable influence on computational accuracy. As number of elements and DOFs increases, the ratio of time consumed in the formation of the Jacobian to that consumed in the solution of algebraic equations tends to decrease. The introduction of parallel solver can yield a substantial reduction in computational cost. Combination of PSTP and PF can give rise to a further significant reduction. The acceleration ratios associated with PSTP do not exhibit a significant decrease as PGA level increases. Even PGA level is equal to 2.0g, PSTP still can result in acceleration ratios of 2.56 and 1.92 for S1 and S4, respectively. It is verified that it is more effective to accelerate analysis by reducing the time spent in solving algebraic equations rather than reducing that spent in the formation of the Jacobian for super high-rise buildings

Hierarchical Ni-Mn LDHs@CuC\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e4\u3c/sub\u3e Nanosheet Arrays-Modified Copper Mesh: A Dual-Functional Material for Enhancing Oil/Water Separation and Supercapacitors

The pursuit of superhydrophilic materials with hierarchical structures has garnered significant attention across diverse application domains. In this study, we have successfully crafted Ni-Mn LDHs@CuC2O4 nanosheet arrays on a copper mesh (CM) through a synergistic process involving chemical oxidation and hydrothermal deposition. Initially, CuC2O4 nanosheets were synthesized on the copper mesh, closely followed by the growth of Ni-Mn LDHs nanosheets, culminating in the establishment of a multi-tiered surface architecture with exceptional superhydrophilicity and remarkable underwater superoleophobicity. The resultant Ni-Mn LDHs@CuC2O4 CM membrane showcased an unparalleled amalgamation of traits, including superhydrophilicity, underwater superoleophobicity, and the ability to harness photocatalytic forces for self-cleaning actions, making it an advanced oil-water separation membrane. The membrane’s performance was impressive, manifesting in a remarkable water flux range (70 kL•m-2•h-1) and an efficient oil separation capability for both oil/water mixture and surfactant-stabilized emulsions (below 60 ppm). Moreover, the innate superhydrophilic characteristics of the membrane rendered it a prime candidate for deployment as a supercapacitor cathode material. Evidenced by a capacitance of 5080 mF•cm-2 at a current density of 6 mA cm-2 in a 6MKOH electrolyte, the membrane’s potential extended beyond oil-water separation. This work not only introduces a cutting-edge oil-water separation membrane and supercapacitor electrode but also offers a promising blueprint for the deliberate engineering of hierarchical structure arrays to cater to a spectrum of related applications

Three-dimensional coupled dynamic analysis of deep ocean mining system

Razvijen je novi trodimenzionalno spregnuti dinamički model sustava za rudarenje u dubokom oceanu. Kopač koji se vuče po dnu napravljen je kao 3D model kompaktnog vozila s mehaničkim modelom gusjeničara s elementima u zahvatu, s kojim ne samo da se može ostvariti brza dinamička simulacija nasuprot tradicionalnom 3D modelu sastavljenom od više dijelova, već se može također omogućiti nošenje specijalnog terramehaničkog modela za talog s morskog dna. Cjevovod za kopanje izrađen je kao 3D model diskretnih elemenata s više dijelova koji je podijeljen u krute elemente povezane fleksibilnim konektorima, i može također ostvariti brzu dinamičku simulaciju za tako dugačak cjevovod. Predloženi su i simulirani novi integrirani načini iskapanja za čitav sustav koji pokazuju da se kroz cijeli postupak može dobro održati stabilno sinhronizirano djelovanje čitavog sustava. Dinamička simulacijska analiza data u radu može pružiti važnu teoretsku bazu i tehničku referencu za dizajn konstrukcije, ocjenu djelovanja i kontrolu rada praktičnog sustava iskapanja u dubokom oceanu.A new three-dimensional coupled dynamic model of the deep ocean mining system is developed. The seafloor tracked miner is built as a 3D single-body vehicle model with mesh element track-terrain interaction mechanics model, which not only can realize the fast dynamic simulation in contrast to traditional 3D multi-body model, but also can allow the loading of the seafloor sediment special terramechanics model. The mining pipeline is built as a 3D multi-body discrete element model that is divided into rigid elements linked by flexible connectors, also can realize the fast dynamic simulation for such long pipeline. New integrated mining operation modes for the total system are proposed and simulated, which show that during the whole operation processes, the synchronized stable motion of the total system can be kept well. The dynamic simulation analysis in the paper can provide important theoretical basis and technical reference for structure design, performance evaluation and operation control of the practical deep ocean mining system

Characterization of Antibiotics and Antibiotic Resistance Genes on an Ecological Farm System

There is a growing concern worldwide about the prevalence of antibiotics and antibiotic resistance genes (ARGs) on the farm. In this study, we investigated the distribution of seven antibiotics and ten ARGs in fresh and dried pig feces, in biogas slurry, and in grapeplanting soil from an ecological farm. Antibiotics including sulfamethazine, norfloxacin, ofloxacin, tetracycline, oxytetracycline, and chlortetracycline were detected in these samples (except for sulfamethoxazole) in dried feces. In general, antibiotics levels in samples were in the sequence: biogas slurry > fresh feces > soil or dried feces. Results of ecological risk assessments revealed that among the seven antibiotics chlortetracycline showed the highest ecological risk. Among the ten ARGs, sulI and tetO were the most prevalent on this ecological farm. There were positive correlations between certain ARGs and the corresponding antibiotics on this ecological farm. Therefore, continuous monitoring of antibiotics and their corresponding ARGs should be conducted in the agroecosystem near the concentrated animal farming operation systems

Application of stimuli-responsive nanomedicines for the treatment of ischemic stroke

Ischemic stroke (IS) refers to local brain tissue necrosis which is caused by impaired blood supply to the carotid artery or vertebrobasilar artery system. As the second leading cause of death in the world, IS has a high incidence and brings a heavy economic burden to all countries and regions because of its high disability rate. In order to effectively treat IS, a large number of drugs have been designed and developed. However, most drugs with good therapeutic effects confirmed in preclinical experiments have not been successfully applied to clinical treatment due to the low accumulation efficiency of drugs in IS areas after systematic administration. As an emerging strategy for the treatment of IS, stimuli-responsive nanomedicines have made great progress by precisely delivering drugs to the local site of IS. By response to the specific signals, stimuli-responsive nanomedicines change their particle size, shape, surface charge or structural integrity, which enables the enhanced drug delivery and controlled drug release within the IS tissue. This breakthrough approach not only enhances therapeutic efficiency but also mitigates the side effects commonly associated with thrombolytic and neuroprotective drugs. This review aims to comprehensively summarize the recent progress of stimuli-responsive nanomedicines for the treatment of IS. Furthermore, prospect is provided to look forward for the better development of this field