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High-performance sodium storage at low temperature is urgent with the increasingly stringent demand for energy storage systems. However, the aggravated capacity loss is induced by the sluggish interfacial kinetics, which originates from the interfacial Na+ desolvation. Herein, all-fluorinated anions with ultrahigh electron donicity, trifluoroacetate (TFA-), are introduced into the diglyme (G2)-based electrolyte for the anion-reinforced solvates in a wide temperature range. The unique solvation structure with TFA- anions and decreased G2 molecules occupying the inner sheath accelerates desolvation of Na+ to exhibit decreased desolvation energy from 4.16 to 3.49 kJ mol-1 and 24.74 to 16.55 kJ mol-1 beyond and below -20 °C, respectively, compared with that in 1.0 M NaPF6-G2. These enable the cell of Na||Na3V2(PO4)3 to deliver 60.2% of its room-temperature capacity and high capacity retention of 99.2% after 100 cycles at -40 °C. This work highlights regulation of solvation chemistry for highly stable sodium-ion batteries at low temperature.
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Aprotic Li-O2 batteries are a promising energy storage technology, however severe side reactions during cycles lead to their poor rechargeability. Herein, highly reactive singlet oxygen (1O2) is revealed to generate in both the discharging and charging processes and is deterimental to battery stability. Electron-rich triphenylamine (TPA) is demonstrated as an effective quencher in the electrolyte to mitigate 1O2 and its associated parasitic reactions, which has the tertiary amine and phenyl groups to manifest excellent electrochemical stability and chemical reversibility. It reacts with electrophilic 1O2 to form a singlet complex during cycles, and it then quickly transforms to a triplet complex through nonradiative intersystem crossing (ISC). This efficiently accelerates the conversion of 1O2 to the ground-state triplet oxygen to eliminate its derived side reactions, and the regeneration of TPA. These enable the Li-O2 battery with obviously reduced overvoltages and prolonged lifetime for over 310 cycles when coupled with a RuO2 catalyst. This work highlights the ISC mechanism to quench 1O2 in Li-O2 battery.
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Li-O2 batteries provide a novel technology for electric energy storage due to their high energy density. However, the strong solvent coordination with Li+ at low temperatures impacts their performance and triggers irreversible interfacial reactions on the Li anode. Herein, cyclopentyl methyl ether (CME) is incorporated in a dimethoxyethane (DME)-based electrolyte to realize an anionic solvation transition at low temperatures in Li-O2 batteries. CME featuring a single O coordination site substitutes highly solvating DME in the first solvation sheath, and it induces more anion coordination to Li+ across the room- and low-temperature ranges. The low residence time of CME (66 ps at 25 °C, 382 ps at -40 °C.) in the solvation structures leads to the fast exchange of coordinated CME molecules with Li+ in comparison with DME and facilitates Li+ desolvation at low temperatures. The simultaneously generated inorganic-rich solid electrolyte interphase promotes Li+ transport to improve Li deposition and suppress Li dendrite formation. These enable the Li-O2 battery to present a good cycling stability of 110 cycles with a fixed capacity of 1000 mA h g-1 at -40 °C. This work paves the way for designing novel electrolytes in low-temperature batteries.
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Aprotic Li-O2 battery has attracted considerable interest for high theoretical energy density, however the disproportionation of the intermediate of superoxide (O2 - ) during discharge and charge leads to slow reaction kinetics and large voltage hysteresis. Herein, the chemically stable ruthenium tris(bipyridine) (RB) cations are employed as a soluble catalyst to alternate the pathway of O2 - disproportionation and its kinetics in both the discharge and charge processes. RB captures O2 - dimer and promotes their intramolecular charge transfer, and it decreases the energy barrier of the disproportionation reaction from 7.70 to 0.70â kcal mol-1 . This facilitates the discharge and charge processes and simultaneously mitigates O2 - and singlet oxygen related side reactions. These endow the Li-O2 battery with reduced discharge/charge voltage gap of 0.72â V and prolonged lifespan for over 230 cycles when coupled with RuO2 catalyst. This work highlights the vital role of superoxide disproportionation for Li-O2 battery.
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Morphological anisotropic engineering is powerful to synthesize metal-organic frameworks (MOFs) with versatile physicochemical properties for diverse applications ranging from gas storage/separation to electrocatalysis and batteries, etc. Herein, we developed a carbon substrate guided strategy to manipulate the facet-dependent coordination for morphology engineering of Fe-THBQ (tetrahydroxy-1,4-benzoquinone) frameworks, which is built with cubic Fe octamer bridged by two parallel THBQ ligands along three orthogonal axes, extending to a three-dimensional (3D) framework with pcu-e network topology. The electronegative O-containing functional groups on carbon surfaces compete with THBQ linkers to selectively interact with the unsaturated coordinated Fe cations on the {111} facets and inhibit crystal growth along the <111> direction. The morphology of Fe-THBQ evolves from thermodynamically favored truncated cube to cuboctahedron depending on the content of O-containing functional groups on the carbon substrate. The Fe-THBQ with varied morphologies exhibits facet-dependent performances for electrochemical lithium storage. This work will shed light on the morphology modulation of MOFs for promising applications.
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The sodium extraction/insertion in layered transition-metal oxide (TMO) cathode materials are typically accompanied by slab sliding and lattice changes, leading to microstructure destruction and capacity decay. Herein, negative lattice expansion is observed in an O3 type Ni-based layered cathode of Na0.9 Ni0.32 Zn0.08 Fe0.1 Mn0.3 Ti0.2 O2 upon Na+ extraction. It is attributed to the weak Zn2+ -O2- orbital hybridization and increased electron density of the surrounding oxygen for reinforced interlayer O-O repulsive force. This enables gliding of TMO slabs for the intergrowth phase transition of P3âOP2 to alleviate lattice strain with moderate lattice shrinkage, which exhibits general interslab spacings and volume changes as low as 2.4 % and 1.9 %, respectively. The strong Ti-O bonds accommodate the internal distortion of TMO6 octahedra due to the flexibility of TiO6 octahedra during cycling. These endow a high specific capacity of 144.9â mAh g-1 and excellent cycling performance of pouch-type sodium-ion batteries with 93 % capacity retention after 3600â cycles.
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Sodium-ion batteries (SIBs) are recognized as promising energy storage devices. However, they suffer from rapid capacity decay at ultra-low temperatures due to high Na+ desolvation energy barrier and unstable solid electrolyte interphase (SEI). Herein, a weakly solvating electrolyte (WSE) with decreased ion-dipole interactions is designed for stable sodium storage in hard carbon (HC) anode at ultra-low temperatures. 2-methyltetrahydrofuran with low solvating power is incorporated into tetrahydrofuran to regulate the interactions between Na+ and solvents. The reduced Na+-dipole interactions facilitate more anionic coordination in the first solvation sheath, which consistently maintains anion-enhanced solvation structures from room to low temperatures to promote inorganic-rich SEI formation. These enable WSE with a low freezing point of -83.3 °C and faster Na+ desolvation kinetics. The HC anode thus affords reversible capacities of 243.2 and 205.4â mAh g-1 at 50â mA g-1 at -40 and -60 °C, respectively, and the full cell of HC||Na3V2(PO4)3 yields an extended lifespan over 250 cycles with high capacity retention of ~100 % at -40 °C. This work sheds new lights on the ion-dipole regulation for ultra-low temperature SIBs.
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Glioblastoma (GBM) is the most prevalent and fatal form of brain tumor, which is associated with a poor prognosis. ATP-binding cassette subfamily F member 1 (ABCF1) is an E2 ubiquitin-conjugating enzyme, which is implicated in regulating immune responses and tumorigenesis. Aberrant E3 ubiquitylation has been evidenced in GBM. However, the role of ABCF1 in GBM needs to be further explored. The expression of ABCF1, CXC chemokine ligand 12 (CXCL12), and CXC chemokine receptor 4 (CXCR4) in GBM tissues was examined by the GEPIA tool, real-time PCR and Western blotting. HMC3, U251MG, and LN-229 cells were cultured and transfected with shRNA targeting ABCF1 and ABCF1 plasmids. The proliferative, migrative, and invasive ability of cells was detected. Western blotting was used to detect the levels of phosphorylated phosphatidylinositol 3-kinase (PI3K) and phosphorylated protein kinase B (AKT). We observed that GBM tissues had higher ABCF1, CXCL12, and CXCR4 expression levels. The expression levels of CXCL12 and CXCR4 were enhanced by ABCF1 overexpression, which were significantly reversed by silence of ABCF1 in GBM cells. Silencing ABCF1 or CXCR4 inhibition weakened the capacity of GBM cell growth, migration, and invasion, while ectopic ABCF1 expression or CXCL12 treatment enhanced the cellular function of GBM cells. Furthermore, p-PI3K and p-AKT protein levels were downregulated by ABCF1 knockdown or CXCR4 blockade, which were prompted by ABCF1 overexpression or CXCL12 supplement. The ABCF1-CXCL12-CXCR4 axis was identified as a key player in GBM cell survival and metastasis by activating the PI3K/AKT signaling pathway in GBM cells.
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Layered manganese-based oxides (LMOs) are promising cathode materials for sodium-ion batteries (SIBs) due to their versatile structures. However, the Jahn-Teller effect of Mn3+ induces severe distortion of MnO6 octahedra, and the resultant low symmetry is responsible for the gliding of MnO2 layers and then inferior multiple-phase transitions upon Na+ extraction/insertion. Here, hexagonal P2-Na0.643 Li0.078 Mn0.827 Ti0.095 O2 is synthesized through the incorporation of Li and Ti into the distorted orthorhombic P'2-Na0.67 MnO2 to function as a phase-transition-free oxide cathode. It is revealed that Li in both the transition-metal and Na layers enhances the covalency of Mn-O bonds and allows degeneracy of Mn 3d eg orbitals to favor the formation of hexagonal phase, and the high strength of Ti-O bonds reduces the electrostatic interaction between Na and O for suppressed Na+ /vacancy rearrangements. These collectively lead to a whole-voltage-range solid-solution reaction between 1.8 and 4.3 V with a small volume variation of 1.49%. This rewards its excellent cycling stability (capacity retention of 90% after 500 cycles) and rate capability (89 mAh g-1 at 2000 mA g-1 ).
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Sulfide-sulfoxide aerobic photo-oxidation is of great interest in organic and medicinal chemistry; however, developing efficient and facile heterogeneous photocatalytic systems without additional additives remains challenging. Herein, we intentionally designed and synthesized two polyoxometalate (POM)-based metalloviologen frameworks, formulated as [MII(4-PBPY)2(H2O)][MII(H2O)4][CoIII2MoVI10H4O38]·nH2O (M = Cu, n = 10 for 1; M = Co, n = 11 for 2), prepared by the mild one-step synthesis strategy and characterized in detail. X-ray single-crystal diffraction analysis shows that they present a two-dimensional layered structure formed by two parallel metalloviologen layers pillared by dimeric Evans-Showell-type POMs. The connection of POM to the metalloviologen framework enables easier flow of electrons to the POM port, which can theoretically further induce O2 to generate reactive oxygen species (O2â¢-) to oxidize substrates to form target products. As expected, both 1 and 2 exhibit outstanding photocatalytic activity in the oxidation of sulfides. Within 6 h, methyl phenyl sulfide can be quantitatively converted into methyl phenyl sulfoxide. The in-depth mechanism reveals that there is also a synergistic energy-transfer pathway in the catalytic system in addition to the electron-transfer pathway. In addition, the corresponding catalytic activity and structure can be well maintained after at least 10 cycle experiments.
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Sulfide-containing wastewater, characterized by its foul odor, corrosiveness, and toxicity, can endanger human health. Fluidized-bed homogeneous crystallization (FBHC) avoids the excessive sludge production commonly associated with conventional chemical precipitation methods. In this study, FBHC is used to treat sulfur-containing synthetic wastewater. Furthermore, nickel-containing wastewater was utilized as a precipitant in the system, hence the advantage of simultaneous sulfur and nickel removal from the wastewater. The operating parameters, including pH, a precipitant dosage of [Ni2+]0/[S2-]0, and cross-sectional surface loading (LS, kg/m2h) are optimized. The optimum operating conditions of pH 9.8 ± 0.3, [Ni2+]0/[S2-]0 = 0.8, and LS = 1.5 kg/m2h results in total sulfur removal (TR) of 95.7% and crystallization ratio (CR) of 94.8%. The effect of organic compounds (acetic acid, oxalic acid, EDTA, and citric acid) and inorganic ions (NO3-, CO32-, PO43-, F-, and Cl-) on the nickel sulfide granulation process was discussed.
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Hard carbon (HC) is a promising anode material for sodium-ion batteries, yet still suffers from low initial Coulombic efficiency (ICE) and unstable solid electrolyte interphase (SEI). Herein, sodium diphenyl ketone (Na-DK) is applied to realize dual-function presodiation for HC anodes. It compensates the irreversible Na uptake at the oxygen-containing functional groups and reacts with carbon defects of five/seven-membered rings for quasi-metallic sodium in HC. The as-formed sodium induces robust NaF-rich SEI on HC in 1.0â M NaPF6 in diglyme, favoring the interfacial reaction kinetics and stable Na+ insertion and extraction. This renders the presodiated HC (pHC) with high ICE of ≈100 % and capacity retention of 82.4 % after 6800â cycles. It is demonstrated to couple with Na3 V2 (PO4 )3 cathodes in full cells to show high capacity retention of ≈100 % after 700â cycles. This work provides in-depth understanding of chemical presodiation and a new strategy for highly stable sodium-ion batteries.
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Li-O2 batteries have garnered much attention due to their high theoretical energy density. However, the irreversible lithium plating/stripping on the anode limits their performance, which has been paid little attention. Herein, a solvation-regulated strategy for stable lithium anodes in tetraethylene glycol dimethyl ether (G4) based electrolyte is attempted in Li-O2 batteries. Trifluoroacetate anions (TFA- ) with strong Li+ affinity are incorporated into the lithium bis(fluorosulfonyl)imide (LiTFSI)/G4 electrolyte to attenuate the Li+ -G4 interaction and form anion-dominant solvates. The bisalt electrolyte with 0.5â M LiTFA and 0.5â M LiTFSI mitigates G4 decomposition and induces an inorganic-rich solid electrolyte interphase (SEI). This contributes to decreased desolvation energy barrier from 58.20 to 46.31â kJ mol-1 , compared with 1.0â M LiTFSI/G4, for facile interfacial Li+ diffusion and high efficiency. It yields extended lifespan of 120â cycles in Li-O2 battery with a limited Li anode (7â mAh cm-2 ). This work gains comprehensive insights into rational electrolyte design for Li-O2 batteries.
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Rechargeable lithium-oxygen batteries (LOBs) are considered to be the next-generation energy technology owing to their high theoretical energy density. However, the sluggish cathode kinetics and degradation of Li anodes result in large voltage hysteresis and low coulombic efficiency. Various materials have been applied to promote the electrochemical performance of LOBs. Metal-organic frameworks (MOFs) possessing porous structures, open active sites and adjustable pore sizes have been attempted as promising materials for catalysts and separators of LOBs. This concept presents an overview of different MOF-based catalysts for LOBs, including traditional, conductive, semi-conductive and soluble MOFs, as well as our recently proposed photo-involved LOBs. Recent advances in MOF-based separators to restrain the shuttling of redox mediators between cathodes and anodes and suppress the formation of lithium dendrites are also discussed. Finally, perspectives on the development of MOF-based LOBs for future research are presented.
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The development of visible-light photocatalysts for the selective oxidative coupling of amines to imines is an area of great interest. Herein, four hybrid compounds based on polyoxometalate anions and tris(bipyridine)ruthenium cations, Ru(bpy)3[M6O19] (M = Mo, W) 1-2, [Ru(bpy)3]2[Mo8O26] 3, [Ru(bpy)3]2[W10O32] 4, are prepared and characterized by X-ray diffraction (single-crystal and powder), elemental analysis, energy-dispersive X-ray spectroscopy (EDS) analysis, infrared (IR) spectroscopy, and solid diffuse reflective spectroscopy. Single-crystal structural analysis indicates that polyoxometalate anions and tris(bipyridine)ruthenium cations interact with each other through extensive hydrogen bonds in these compounds. These hybrid species with strong visible-light-harvesting abilities and suitable photocatalytic energy potentials show excellent photocatalytic activity and selectivity for the oxidation of amines to imines at room temperature in air as an oxidant. Among them, compound 1 with the [Mo6O19]2- anion has the highest catalytic activity, which can swiftly convert >99.0% of benzylamine into N-benzylidenebenzylamine with a selectivity of 98.0% in 25 min illumination by a 10 W 445 nm light-emitting diode (LED). Its turnover frequency reaches 392 h-1, which is not only better than the homogeneous catalyst [Ru(bpy)3]Cl2 but also much superior to those achieved over most of reported heterogeneous catalysts. Moreover, it shows a wide generality for various aromatic amines, accompanied by the advantages of good recyclability and stability. The photocatalytic oxidation mechanism of amines to the corresponding imines over polyoxometalate-based hybrid compounds was fully investigated.
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Hematological diseases, including leukemia, lymphoma, and multiple myeloma, are characterized by high heterogeneity with diverse cellular subpopulations. Single-cell RNA sequencing (scRNA-seq), a transformational technology, provides deep insights into cell-to-cell variation in tumor and microenvironment, allows high-resolution dissection of the pathogenic mechanisms of diseases, and affords potential clinical utilities. Recent developments in single-cell transcriptomics and associated technologies and their applications in hematological disorders for unraveling cellular subpopulations, disease pathogenesis, patient stratification, and therapeutic responses are summarized.
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Doenças Hematológicas , Análise de Sequência de RNA , Análise de Célula Única , Sequência de Bases , Biologia Computacional , Humanos , ProteômicaRESUMO
Cocrystals are often more soluble than needed and pose unnecessary risks for precipitation of less soluble forms of the drug during processing and dissolution. Such conversions lead to erratic cocrystal behavior and nullify the cocrystal solubility advantage over parent drug (SA = Scocrystal/Sdrug). This work demonstrates a quantitative method for additive selection to control cocrystal disproportionation based on cocrystal solubility advantage (SA) diagrams. The tunability of cocrystal SA is dependent on the selective drug-solubilizing power of surfactants (SPdrug = (ST/Saq)drug). This cocrystal property is used to generate SA-SP diagrams that facilitate surfactant selection and provide a framework for evaluating how SA influences drug concentration-time profiles associated with cocrystal dissolution, drug supersaturation, and precipitation (DSP). Experimental results with indomethacin-saccharin cocrystal and surfactants (sodium lauryl sulfate, Brij, and Myrj) demonstrate the log-linear relationship characteristic of SA-SP diagrams and the dependence of σmax and dissolution area under the curve (AUC) on SA with characteristic maxima at a threshold supersaturation where drug nucleation occurs. This approach is expected to streamline cocrystal formulation as it facilitates additive selection by considering the interplay between thermodynamic (SA) and kinetic (DSP) processes.
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Precipitação Química , Liberação Controlada de Fármacos , Indometacina/química , Óleos de Plantas/química , Polietilenoglicóis/química , Sacarina/química , Dodecilsulfato de Sódio/química , Tensoativos/química , Área Sob a Curva , Cristalização , Concentração de Íons de Hidrogênio , Cinética , Concentração Osmolar , Solubilidade , TemperaturaRESUMO
PURPOSE: To explore the spiritual needs of community-dwelling older people living with early-stage dementia. DESIGN: A descriptive qualitative research design with purposive sampling was used. METHODS: Ten older people who were receiving home care services from a mental hospital in central Taiwan were recruited. In-depth semistructured interviews were conducted and content analysis was performed. FINDINGS: Four themes emerged that described the spiritual wishes and needs of older people with early-stage dementia: the wish to turn back time, the need to instill meaning into past experiences, the need to rely on faith-based strength, and the wish to have one's remaining life under control. The spiritual needs centered on a strong yearning to engage in a tug-of-war with time to reverse the impaired memory and independence. CONCLUSIONS: This study provides insights into the spiritual needs of older people with early-stage dementia. They struggled to maintain a balance between independence and dependence, build a sense of self and value, seek guidance and support from religious faith, and retain control over their lives. CLINICAL RELEVANCE: The findings can be expected to help caregivers improve care of older people with dementia by empowering older people to hold onto control in their lives and providing opportunities for them to connect with others for fulfilling their spiritual needs.
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Demência/psicologia , Serviços de Assistência Domiciliar , Espiritualismo/psicologia , Idoso , Idoso de 80 Anos ou mais , Cuidadores , Demência/enfermagem , Feminino , Humanos , Vida Independente , Masculino , Pesquisa Qualitativa , TaiwanRESUMO
Due to heterogeneous morphological and immunophenotypic features, approximately 50% of peripheral T-cell lymphomas are unclassifiable and categorized as peripheral T-cell lymphomas, not otherwise specified. These conditions have an aggressive course and poor clinical outcome. Identification of actionable biomarkers is urgently needed to develop better therapeutic strategies. Epigenetic alterations play a crucial role in tumor progression. Histone modifications, particularly methylation and acetylation, are generally involved in chromatin state regulation. Here we screened the core set of genes related to histone methylation (KMT2D, SETD2, KMT2A, KDM6A) and acetylation (EP300, CREBBP) and identified 59 somatic mutations in 45 of 125 (36.0%) patients with peripheral T-cell lymphomas, not otherwise specified. Histone modifier gene mutations were associated with inferior progression-free survival time of the patients, irrespective of chemotherapy regimens, but an increased response to the histone deacetylase inhibitor chidamide. In vitro, chidamide significantly inhibited the growth of EP300-mutated T-lymphoma cells and KMT2D-mutated T-lymphoma cells when combined with the hypomethylating agent decitabine. Mechanistically, decitabine acted synergistically with chidamide to enhance the interaction of KMT2D with transcription factor PU.1, regulated H3K4me-associated signaling pathways, and sensitized T-lymphoma cells to chidamide. In a xenograft KMT2D-mutated T-lymphoma model, dual treatment with chidamide and decitabine significantly retarded tumor growth and induced cell apoptosis through modulation of the KMT2D/H3K4me axis. Our work thus contributes to the understanding of aberrant histone modification in peripheral T-cell lymphomas, not otherwise specified and the stratification of a biological subset that can benefit from epigenetic treatment.
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Proteínas de Ligação a DNA/metabolismo , Genes Modificadores/genética , Histonas/metabolismo , Linfoma de Células T Periférico/tratamento farmacológico , Linfoma de Células T Periférico/genética , Mutação , Proteínas de Neoplasias/metabolismo , Acetilação , Aminopiridinas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Benzamidas/farmacologia , Linhagem Celular Tumoral , Análise Mutacional de DNA , Decitabina/farmacologia , Xenoenxertos , Histonas/genética , Humanos , Linfoma de Células T Periférico/mortalidade , Metilação , Camundongos , Prognóstico , Análise de Sobrevida , Células Tumorais CultivadasRESUMO
In this study, a fluidized bed reactor was used to compare heterogeneous and homogeneous crystallization for recovering magnesium ammonia phosphate (MAP) from the dewatering filtrate at a municipal water resource recovery facility. Investigating the factors affecting crystallization revealed that pH exerted a greater effect than the Mg/P molar ratio. The results of a heterogeneous crystallization experiment showed that removal efficiency of phosphate (RP%) and crystal efficiency of phosphate (CP%) were 68% and 66%, respectively, at a PO4-P concentration of 200 mg/L, pH of 8.0, and Mg/P molar ratio of 1.0 for 3 h. The reaction rate of heterogeneous crystallization was markedly higher than that of homogeneous crystallization. Those pellets produced through the heterogeneous crystallization exhibited a dense surface (particle size 0.5-1.0 mm; water content 8.7%). Through scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), and X-ray diffraction (XRD) examination, the crystallized patterns of the needle-shaped pellets were identified as MgNH4PO4·6H2O.