Forms Of ALP Research Articles

Strategy for clean phosphate recovery from polymerized aluminum chloride-treated sludge by alkaline anion exchange resins: High alkalinity and desorption

Polyaluminum chloride (PAC) is commonly used as a flocculant in wastewater treatment plants to aid in the removal of phosphorus (P) from wastewater. As a result, the P element present in PAC-treated sludge is predominantly in the form of Al-P. This study proposes the use of alkaline anion exchange resin (AAER) as a pretreatment method for PAC-treated sludge to enhance P extraction and achieve cleaner P recovery from this type of sludge. The findings of the study indicate that the optimal concentration of AAER is 12 g/g TS, resulting in a P extraction efficiency of 67.2 %. This represents a 26.5 % increase compared to alkali treatment at the same pH (pH = 12.23). Stepwise extraction analysis and molecular dynamics simulations suggest that during AAER treatment, Al(OH)3 is converted into dissolved [Al(OH)4]−. These species then agglomerate with PO43− and subsequently get adsorbed by the N(CH3)+ groups on the AAER. Furthermore, even after undergoing five regeneration cycles, the AAER still exhibits a significant adsorption capacity for P. Ultimately, high-purity Ca10(PO4)6(OH)2 is obtained as the final product with a recovery rate of 90.5 %. Meanwhile, the Al extracted by AAER can be reused as a feedstock for polymerized aluminum chloride. This demonstrates that AAER extraction is a promising and efficient waste management strategy for the clean recovery of P and Al from PAC sludge.

Pengaruh Pemberian Zeolit Alam Teraktivasi terhadap Sifat Kimia Tanah Podsolik

Podsolic soil in South Kalimantan has a low fertility rate including pH, organic matter, cation exchange capacity (CEC), solubility P, and has a high solubility of aluminum (Al) and iron (Fe). It causes fixation P by Al and Fe in the form of Al-P and Fe-P, which makes P difficult to dissolve in the soil. Zeolite is an ameliorant that is capable of improving soil chemical properties based on its ability to carry out ion exchange, adsorption, absorb molecules, increase fertilizer efficiency, increase soil CEC, and the availability of Ca, K, and P ions, which can reduce aluminum content. The purpose of this study was to identify the pattern of relationships caused by application of activated natural zeolite on Podsolic soil against pH, CEC, available P, soluble Fe, and exchangeable Al. This study was a pot experiment weighing 0.5 kg of soil, carried out in a greenhouse and arranged using CRD a single factor . The incubation period was carried out for eight weeks with three replications. The results showed that there was a relationship between the zeolite dose activated against the available P (the linear regression equation Y = 0.6 + 0.032 X, R2 = 0.4969, and r = 0.7006*), while the doses of zeolite had no significant effect on pH, CEC, soluble Fe, and exchangeable Al.

The Structural Evolution of Al-6Y-2P Master Alloy and its Influence on the Refinement of Mg<sub>2</sub>Si Phase in Mg<sub>2</sub>Si/Al Composites

In this article, a novel Al–6Y–2P master alloy with YP particles was successfully synthesized. By means of the fracture surface observation, it was found that YP particles with an average size of 21.5 μm exhibit the cubic morphologies. With the addition of Al–6Y–2P master alloy, primary Mg2Si particles in Al–Mg2Si composites can be significantly refined to 21.2 μm and 20.3 μm after holding for 30 min and 120 min respectively. Meanwhile, the morphologies of eutectic Mg2Si alter from a flake-like to fine fibrous shape. The reason for the excellent refining performance of this master alloy was discussed based on the chemical kinetics theory. During the solidification process, P atoms distribute homogeneously in the Al melt and precipitate in the form of AlP, providing heterogeneous nucleation sites for primary Mg2Si.

Sample Complexity and Performance Bounds for Non-Parametric Approximate Linear Programming

One of the most difficult tasks in value function approximation for Markov Decision Processes is finding an approximation architecture that is expressive enough to capture the important structure in the value function, while at the same time not overfitting the training samples. Recent results in non-parametric approximate linear programming (NP-ALP), have demonstrated that this can be done effectively using nothing more than a smoothness assumption on the value function. In this paper we extend these results to the case where samples come from real world transitions instead of the full Bellman equation, adding robustness to noise. In addition, we provide the first max-norm, finite sample performance guarantees for any form of ALP. NP-ALP is amenable to problems with large (multidimensional) or even infinite (continuous) action spaces, and does not require a model to select actions using the resulting approximate solution.

Refinement of Hypereutectic Al–Si Alloy by a New Al–Sc–P Master Alloy

In this article, a novel Al–Sc–P master alloy with ScP particles was successfully synthesized. The XRD result identifies that the Al–1Sc–1P master alloy is composed of two phases, i.e. α-Al and ScP. The microstructure analysis shows that ScP present grey granular particles with 6.5 μm in size. The reason for the excellent refining performance of this master alloy is discussed based on the chemical kinetics theory. During the solidification process, P which dissolved homogeneously in the melt bonded with Al and precipitated in the form of AlP, providing heterogeneous nucleation sites for primary Si.

Properties of phosphorus retention in sediments under different hydrological regimes: A laboratory-scale simulation study

Summary Excessive nutrient loading and changing hydrological regimes can significantly impact the ecological function of wetland ecosystems. Three wetland sediment samples collected from West Lake, Xiazhuhu Wetland and Baoyang River in the Taihu Lake Watershed, China, were compared to understand the P retention properties responding to hydrological regimes by using static column and steady-flow flume laboratory-scale experiments. Sediment in Xiazhuhu Wetland currently function as a P sink with equilibrium P concentration (EPC 0 ) values of 0.010 mg L −1 , while sediments from West Lake and Baoyang River, have EPC 0 values of 0.050 mg L −1 and 0.023 mg L −1 , respectively, and serve as an internal P source. The P retention by sediments ranged from 17.20 to 22.61 mg m −2 d −1 under 35-d static conditions, while sediment beds continuously fed by the simulated inflow water containing 2 mg L −1 P ranged from 59.20 to 171.93 mg m −2 d −1 . The P removal capacities by sediments were higher during the rainy season than the dry season when wetlands were subjected to excessive P input. Since the majority of external P stored in sediment is in the form of Al-P (e.g., for Xiazhuhu wetland), the application of alum to water column could potentially increase the P retention capacity of sediment.

Interpretation and Clinical Significance of Alkaline Phosphatase Isoenzyme Patterns

Alkaline phosphatase (ALP, EC 3.1.3.1) is a membrane-bound metalloenzyme that consists of a group of true isoenzymes, all glycoproteins, encoded for by at least four different gene loci: tissue-nonspecific, intestinal, placental, and germ-cell ALP. Through posttranslational modifications of the tissue-nonspecific gene, for example, through differences in carbohydrate composition, bone and liver ALP are formed. Nowadays, most commercially available methods for separating or measuring ALP isoenzymes are easy to perform and sensitive and allow for reproducible and quantitative results. As more isoenzymes and isoforms have been characterized, confusion has arisen due to the many different names they were given. For the sake of simplicity and because of structural analogies, we propose an alternative nomenclature for the ALP isoenzymes and isoforms based on their structural characteristics: soluble, dimeric (Sol), anchor-bearing (Anch), and membrane-bound (Mem) liver, bone, intestinal, and placental ALP. Together with lipoprotein-bound liver ALP and immunoglobulin-bound ALP, these names largely fit the many forms of ALP one can encounter in human serum and tissues. The clinically relevant isoenzymes are sol-liver, Mem-liver, lipoprotein-bound liver, and Sol-intestinal ALP in liver diseases, and Sol-bone and Anch-bone ALP in bone diseases. Many different isoenzyme patterns can be found in malignancies and renal diseases. This test provides the clinician with valuable information for diagnostic purposes as well as for follow-up of patients and monitoring of treatment. However, ALP isoenzyme determination will only provide clinically useful information if the patterns are correctly interpreted. In this respect, care should be taken to use the proper reference ranges, taking into account the age and sex of the patient. A normal total ALP activity does not rule out the presence of an abnormal isoenzyme pattern, particularly in children. Separating ALP into its isoenzymes adds considerable value to the mere assay of total ALP activity.