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Segmented multiblock polyolefin compatibilizers from non-living metathesis chain-shuffling
Abstract The mechanical properties of mixed plastics can be enhanced by block copolymer compatibilizer additives. Here we report a series of semi-crystalline/semi-crystalline linear multiblock copolymers of LLDPE and PP, the two most abundant plastics, from a non-living shuffling polymerization. Containing up to 13 individual blocks of PE and PP randomly arranged, the multiblock connectivity, crystallinity, and morphology are characterized with a combination of NMR, DSC, X-ray scattering, microscopy, and theoretical models. We show these semi-crystalline products compatibilize and toughen blends of the two most abundant plastics with an enhancement of tensile modulus. Due to the highly segmented nature of the multiblock copolymers, the crystalline morphology exhibits minimal phase separation and imbibes the amorphous chains in commercial polymer interfaces into the semi-crystalline block copolymer phase by transmission electron microscopy. The work provides access to compatibilizer designs that implement a combination of tie-chain, trapped entanglement, and co-crystallization reinforcement mechanisms for toughening post-consumer blends.
Novel approximate solutions of the fractional form of graphene sheet thermophoretic motion model
The response of meteorological drought to extreme climate in the water-receiving area of the Tao river diversion project in China
Towards decoding individual words from non-invasive brain recordings
Abstract While deep learning has enabled the decoding of language from intracranial brain recordings, achieving this with non-invasive recordings remains an open challenge. We introduce a deep learning pipeline to decode individual words from electro- (EEG) and magneto-encephalography (MEG) signals. We evaluate our approach on seven public datasets and two datasets which we collect ourselves, amounting to a total of 723 participants reading or listening to five million words in three languages. Our model outperforms existing methods consistently across participants, devices, languages, and tasks, and can decode words absent from the training set. Our analyses highlight the importance of the recording device and experimental protocol: MEG and reading are easier to decode than EEG and listening, and decoding performance consistently increases with the amount of data used for training and for averaging during testing. Overall, our findings delineate the path and remaining challenges towards building non-invasive brain decoders for natural language.
Rigid inclusion columns and the composite modulus method for enhancing storage tank foundation bearing capacity
An IoT based remote medical diagnosis system using one time pad cipher over MQTT protocol
The H3K27me3 reader UAD-2 recruits a TAF-12-containing transcription machinery to initiate piRNA expression within heterochromatic clusters
Terpene content in the air of younger and older forests in southeastern Poland: implications for forest therapy
Abstract The aim of the study was to investigate differences in terpene content level in the air within younger and older forests of the same species. Conducted from July 18 to October 2 in Nemoral Scots pine and Central European submontane beech forests, air samples were collected using portable aspirators with Tenax TA sorbent tubes. The compounds were identified and quantified using gas chromatography with flame ionization detection. Results showed that older forests emitted more volatile organic compounds (VOCs) than younger ones. Regardless of forest age or species, α-pinene was the most prevalent terpene, accounting for 7.4–12.9% of total VOCs. Other terpenes, such as β-pinene and camphene, were found in lower concentrations (1.7–12.7 times less). In Scots pine, higher α-pinene concentrations were observed in older forests, while younger forests had higher levels of 3-carene and α-terpinene. For beech, higher concentrations of camphene and β-pinene were found in younger forests. In nearly half of the cases, TVOC values and terpene concentrations showed moderate variability (25–45%), with high variability (> 45%) recorded in the remainder. Considering the quantitative and qualitative structure of terpenes, an older pine forest would be most suitable for supporting the treatment of respiratory diseases.
Nonlinear control of quadrotor UAV under rotor failure for robust trajectory tracking
Abstract We present a trajectory tracking control law for a quadrotor unmanned aerial vehicle (UAV) for handling the complete failure of a single rotor. The control design problem considers the reduced state space, which excludes the angular velocity and orientation about the vertical body axis. The proposed controller enables the quadrotor to track the orientation of this axis and consequently any prescribed position trajectory using only three rotors. The control design is carried out in two stages. First, to track the reduced attitude dynamics, a geometric controller with two input torques is designed on the Lie group SO(3). This controller is then extended to SE(3) by designing a saturation-based feedback law to track the center of mass position with bounded thrust. The control law for the complete dynamics achieves an almost global exponential tracking. The novelty of geometric control design lies in its ability to effectively execute aggressive global maneuvers despite the complete loss of a rotor. Numerical simulations on a conventional quadrotor model, carried out for complete trajectory tracking, together with preliminary experimental tests on a real platform under a hover scenario with sudden motor failure, are presented to demonstrate the practical applicability of the proposed control design.
Indirect methanol synthesis from CO2 through high-efficient dimethyl carbonate hydrogenation as a bridge below 100°C
Microstructure, phase transformation temperatures and long-term stability of ex-situ Alloy 718 + TiB2 metal-ceramic nanocomposites as a repair coatings for aerospace applications
Exploring how green location-oriented industrial policies promote urban energy efficiency: evidence from National eco-industrial demonstration parks in China
Electromagnetic viscosity supported anomalous electric field in the electron diffusion region of collisionless magnetic reconnection
Travel experiences documented in online reviews influence travelers’ travel intentions
Association between body mass index and efficacy of neoadjuvant targeted therapy in HER2-positive breast cancer in a Chinese multicenter cohort
Microproteins Simba1 and Simba2 activate Wingless signaling during the reactivation of neural stem cells in Drosophila
Transport of degradable contaminants in a composite vertical cut-off wall under nonlinear adsorption conditions
Abstract Barrier materials frequently exhibit nonlinear adsorption characteristics for contaminants in leachate, with this nonlinearity becoming increasingly pronounced at higher concentrations. A composite vertical cut-off wall, constructed from an adsorptive soil-bentonite mixture and a geosynthetic clay liner provides an effective solution for barrier systems and emergency responses to organic contaminants. Understanding the transport mechanisms of degradable contaminants (e.g., organic pollutants) within the composite cut-off wall is essential for evaluating barrier effectiveness against contamination. This study established a general theoretical model for the one-dimensional transport of degradable contaminants in the composite vertical cut-off wall, considering nonlinear adsorption, advection, diffusion, mechanical dispersion, and degradation processes during the transport period simultaneously. Parametric studies show that the relative concentrations of degradable contaminants in the composite cut-off wall, based on the Freundlich adsorption assumption, significantly differ from those predicted by the linear adsorption assumption. The influence of the Freundlich adsorption model parameters on contaminant transport and boundary conditions was thoroughly analyzed. The degradation process can effectively reduce the relative concentration of contaminants in the composite cut-off wall. Notably, the time required for the contaminant concentration to traverse the composite cut-off wall and reach the limit value (breakthrough time), when considering degradation ( t 1/2 = 10 a), is 1.7 times that calculated without accounting for degradation. Furthermore, increased permeability of the aquifer under the boundary conditions results in lower contaminant concentrations within the outlet range of the transport model, leading to a corresponding increase in breakthrough time.