Iron Research Articles

FT-IR, XRD, EDX-SEM and Radiological Fingerprints of Sedimentary Rocks of Bodamalai Hills in Tamil Nadu, India

Objectives: To elucidate the minerals and elements available in sedimentary rocks of Bodamalai hills which is located in Namakkal district, Tamil Nadu state, India. To examine the radiological fingerprints of the rock samples. Methods: Fourier Transform Infra-Red (FT-IR) Spectroscopy method was carried out to identify the minerals, X-Ray diffraction (XRD) techniques were used to confirm the presence of minerals and identify the new minerals, and to reveal the chemical composition and morphological studies as well. The Scanning Electron Microscope along with Electron Dispersive X-ray Analysis (SEM-EDX) utilized to detect the presence of elements along with their percentage of weight. The concentration of radionuclides like 40K, 232Th and 238U was determined using High Purity Germanium (HPGe) detector and their amount expressed in Bq kg-1. Findings: The minerals Quartz, Calcite, Cristobalite, Gibbsite, Goethite, Halloysite, Hectorite, Illite, Kaolinite, Lepidocrocite, Microcline Feldspar, Montmorillonite, Nacrite, Organic Compound, Palygorskite, Sepiolite, and Siderite are identified through FT-IR and XRD. The nature of the crystanillity of quartz was not uniform from top to bottom, it was randomly present in elevation wise with a range from 1.07 to 1.44. The elements Carbon, Oxygen, Sodium, Magnesium, Aluminium, Silicon, Potassium, Calcium, Iron and Copper found their percentage of weight with atomic percentage. Silicon and Oxygen were dominant elements in rock material. The amount of radiation exposure of radioactive elements 40K, 232Th and 238U was found. Novelty: The availability of minerals and elements was identified in Bodamalai Hills. The metals Al, Fe, Cu, Mg present in this rock were found and their percentage of availability is Al-5.46%, Fe-1.54%, Cu-0.14% and Mg-0.18%. The radiological results indicate that the radioactivity shows only in 40K (58.8±21.1 Bq kg-1 to 264.1±26.2 Bq kg-1) other elements 232Th, 238U were shown below the detection limit (less than 1 Bq kg-1). Keywords: FTIR, XRD, EDX with SEM, Crystallinity Index, Radiological Fingerprint

Boosting nutritional value: the role of iron fortification in meat and meat products.

Iron deficiency is a widespread nutritional problem affecting millions of people globally, leading to various health issues including anemia. Iron fortification of meat and meat products has emerged as an effective strategy to combat this issue. This review explores the process and benefits of iron fortification, focusing on the types of iron compounds suitable for fortification, such as ferrous sulfate and ferric pyrophosphate, their bioavailability, and their impact on the sensory and nutritional qualities of meat products. Technological challenges and solutions, including encapsulation, chelation, and microencapsulation techniques, have been examined to minimize their negative impacts on sensory qualities. This review also discusses the regulatory framework governing iron fortification and consumer acceptance. Analytical methods for determining iron content, such as spectrophotometric and colorimetric detection, are discussed. Although iron-fortified meat products offer health benefits, sensory aspects and consumer acceptance are important considerations. This review provides a comprehensive understanding of the role and significance of iron fortification in meat products as a public health intervention to address iron deficiency.

An Icosahedral 55-Atom Iron Hydride Cluster Protected by Tri-tert-butylphosphines.

Nanoclusters are nanometer-sized molecular compounds characterized by significant metal-metal bonding and low average oxidation states, and they exhibit unique properties distinct from those of small metal complexes or nanoparticles. Unlike noble metals stable in metallic forms, the synthesis of nanometer-sized iron clusters has been precluded by the relatively weak iron-iron bonds and the high reactivity of low oxidation state iron, despite the extensive history of molecular iron compounds. Here, we report the synthesis and characterization of a cationic 55-atom iron cluster with a 1.2 nm icosahedral core. Its 12 vertices are occupied by tri-tert-butylphosphines, while multiple hydrides cover the surface. This core can be viewed as a substructure of the face-centered cubic (fcc), in contrast to the body-centered cubic (bcc) for the stable bulk phase. This work reveals a stable structure and fundamental properties of a nanometer-sized iron cluster, which have remained elusive for decades, and the simple synthetic protocol provides a route to explore molecular nanochemistry.

Interactions Between Trace Elements and Macro Minerals in Pregnant Heifers

There is a lack of information on mineral interactions that take place during a heifer’s pregnancy when nutrient demand is high. The objective of the present study was to evaluate the interactions between the macro minerals calcium (Ca), phosphorus (P), magnesium (Mg), sulphur (S), sodium (Na) and potassium (K) and the trace elements copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), selenium (Se), zinc (Zn) and cobalt (Co) in pregnant heifers. Twenty-four pregnant heifers (age 18.2 ± 0.14 months; 87.5 ± 4.74 days in gestation; 497 ± 8.5 kg of body weight) were used in a 7 d digestibility trial (indirect method using lignin as a marker) during which they were fed a diet that provided minerals in accordance with NASEM requirements for gestating beef cattle. At the end of the digestibility trial, blood (jugular venipuncture) and liver (biopsy) samples were collected from each heifer. Multiple linear regression models were developed based on the main correlations and by considering collinearity effects between variables. Iron intake positively affected Mo concentration in serum, which was >10 µg/dL for most of the animals. Apparent absorption of Fe was negatively affected by Mo intake and Ca to P ratio in feed, whereas Se absorption was negatively affected by Fe intake and positively by Mo intake. The absorption coefficients of Mo and Fe were inversely related, emphasizing the interactions between these elements. Serum Fe and Cu in the liver were positively correlated, while liver Fe was inversely related to liver Mn. Fewer interactions were observed between the macro minerals. In conclusion, within the interactions observed, those between Fe and Mo deserve special attention, as high dietary Fe is commonly found in typical ruminant diets, and high serum Mo may indicate molybdenosis. Furthermore, high Fe intake appears to impact Se and Mn utilization.

Physico-Chemical Properties of Granular Sorbents Based on Natural Bentonite Modified by Polyhydroxocations of Aluminum and Iron (III) by Co-Precipitation.

The physicochemical and adsorption properties of granular sorbents based on natural bentonite and modified sorbents based on it have been studied. It was found that modification of natural bentonite with iron (III) polyhydroxocations (mod. 1_Fe_5 GA) and aluminum (III) (mod. 1_Al_5 GA) by the "co-precipitation" method leads to a change in their chemical composition, structure, and sorption properties. It is shown that modified sorbents based on natural bentonite are finely porous (nanostructured) objects with a predominance of pores measuring 1.5-8.0 nm, with a specific surface area of 55-65 m2/g. Modification of bentonite with iron (III) and aluminum compounds by the "co-precipitation" method also leads to an increase in the sorption capacity of the obtained sorbents with respect to bichromate and arsenate anions and nickel cations by 5-10 times compared with natural bentonite. The obtained sorption isotherms were classified as Langmuir type isotherms. Kinetic analysis showed that at the initial stage the sorption process is controlled by an external diffusion factor, i.e. refers to the diffusion of sorbent from solution into a liquid film on the surface of the sorbent. Then the sorption process begins to proceed in a mixed diffusion mode, when it limits both the external diffusion factor and the internal diffusion factor (the diffusion of the sorbent to the active centers through the system of pores and capillaries). To determine the contribution of the chemical stage to the rate of adsorption of bichromate and arsenate anions and nickel(II) cations with the studied granular sorbents, kinetic curves were processed using the equations of chemical kinetics (pseudo-second-order model). As a result, it was found that the adsorption of the studied anions by modified sorbents based on natural bentonite is best described by a pseudo-second-order kinetic model. It is shown that the use of natural bentonite for the development of technology for the production of granular sorbents based on it has an undeniable advantage, firstly, in terms of its chemical and structural properties, it is easily and effectively modified, and secondly, having astringent properties, granules are easily made on its basis, which turn into ceramics during high-temperature firing. The result is a granular sorbent with high physical and mechanical properties. Since bentonite is an environmentally friendly product, the technology of recycling spent sorbents is also greatly simplified.

Essential and toxic elements in nail samples from fishermen in Turkey

Toxic substances in seafood can accumulate in consumers and cause serious health problems. The purpose of this research was to evaluate the levels of 11 essential and toxic elements (arsenic, copper, mercury, zinc, iron, cadmium, chromium, lead, nickel, selenium and titanium) in nail samples from fishermen who frequently consumed seafood and control groups who consumed them less frequently. This study was conducted in the Marmara Sea coastal cities of Istanbul, Kocaeli, Tekirdağ and Yalova. 352 individuals were enrolled, 263 fishermen and 89 controls. A questionnaire was administered to the individuals, then fingernail samples were collected. Nail samples were digested by the addition of HNO3 and H2O2, then the element levels was measured by ICP-MS. Zinc and iron levels in fishermen’s nails were higher than in controls. Positive correlations were observed between levels of arsenic, mercury, iron, cadmium, chromium, lead, nickel, selenium, and titanium in the fishermen’s nails and monthly seafood consumption. Mean nail zinc and copper levels were lower than expected in both groups. Other elements were at expected levels. In conclusion, consuming seafood caught in this region does not result in element exposure sufficient to represent a risk, but may increase in the burdens of some elements.

Effect of cryogenic treatment on the mechanical properties of 3D-printed polylactic acid part

The article investigates the effect of cryogenic treatment on the 3-D printed Polylactic Acid (PLA) specimen. It was found that exposure of PLA specimens to the cryogenic temperature (10 K) using a cryocooler led to a 35 % increase in tensile strength in 5 h, with most improvement occurring within the first hour. The cryogenic treatment enhanced the PLA specimen’s strength and ductility due to increased crystallinity and better molecular alignment. It is likely due to the interaction of the cooling medium (helium) used in the cryocooler with the PLA specimens. Towards this, EDS analysis is performed on cryo-treated PLA specimens. The EDS analysis reveals that nickel and iron compounds were detected on the surface of the cryogenic-treated PLA specimen. These findings highlight that cryogenic treatment significantly improves PLA specimen’s mechanical properties and tensile strength. However, challenges arise, including delamination-layer separation caused by internal stresses, and must be addressed. This work will be helpful for researchers working in polymer 3-D printing.

Physicochemical and aromatic properties of iron-enriched tomato paste during storage

In this study, tomato paste was fortified with iron compounds at 25, 50, and 75 ppm concentrations. The effect of adding these micronutrient iron concentrations on the paste’s physical, mechanical, aromatic, and chemical properties was evaluated every 15 days over a 60-day, storage period. The results indicated a gradual decrease in pH, total soluble solids (TSS), and taste index, alongside an increase in total acidity (TA) for all treatments throughout the storage period. The highest lycopene content observed in the Fe-25 % fortified samples at 43.05 mg/kg and the lowest in the control samples at 21.57 mg/kg. Positive values for a* and b* at the beginning and throughout the storage period confirmed the dominance of red and yellow hues in the tomato paste. Viscosity gradually decreased over time. During storage, growth and changes in mold spores and acid-resistant thermophilic bacteria were limited until the 30th day, and total microorganism counts were restricted until the 45th day. The overall accuracy of the support vector machines (C-SVM) and linear discriminant analysis (LDA) method in distinguishing samples into four groups (control, fortified with 25, 50, and 75 ppm iron) were 38 % and 62 % Overall, it can be concluded that increasing the iron micronutrient enhances the nutritional value and positively affects the physical, chemical, and microbial properties and the retention of aromatic compounds in tomato paste.

Accumulation, physiological and proteomic analyses of Suaeda salsa under cadmium exposure.

Suaeda salsa, the dominant herbaceous plant in the high salinity areas of Asia, can even grow in the heavy metal polluted region. In order to illustrate the mechanisms of Cd (cadmium) tolerance in S. salsa, the accumulation, physiological and proteomic characters under two different concentrations of Cd exposure were investigated in this study. The results showed a significant decrease in root and seedling growth rate, as well as an increase in Cd ion content in all tissues of S. salsa, in response to the increased Cd concentration. Furthermore, it was found that Cd was mainly accumulated in the root compared with the stem and leaf. Further proteomic analysis revealed that in the root of S. salsa under 7-d Cd exposure, 260 and 237 proteins were significantly upregulated in 1μg/L and 20μg/L Cd treatment groups, respectively. In addition, Gene Ontology (GO) enrichment analysis showed that cellulose synthase with the function of cell wall organization was upregulated under Cd stress. Moreover, the proteins functioning as the transporters of iron (ATP-binding cassettes protein, metal tolerance proteins, yellow-stripe-like proteins) and organic compounds (oligopeptide transporters, phosphate transporters) were also highly expressed, which indicated that the accumulation of Cd in the root of S. salsa may be mainly regulated through Cd immobilization by the cell wall or transportation into vacuoles. These findings enhance our understanding of the impacts of Cd pollution in S. salsa and may form a basis for future phytoremediation and biomarker studies.

Anisomeles malabarica Leaves: Revisiting Pharmacognostic Features and Taxonomic Paradigms

This study investigates the pharmacognostic and phytochemical properties of Anisomeles malabarica, a medicinal plant from the Lamiaceae family. A comprehensive analysis was performed, encompassing macroscopic, microscopic, and numerical taxonomic studies. The anatomical observations revealed distinctive traits such as unicellular trichomes, collenchymatous and parenchymatous ground tissue, and vascular bundles with concentric arrangements. Quantitative microscopy parameters, including stomatal index and vein islet number, were documented. Physiochemical analyses showed values within Ayurvedic pharmacopeia standards, ensuring the plant's purity and quality. The presence of essential inorganic elements like calcium, potassium, and iron was confirmed, with no detection of toxic heavy metals, underscoring its safety for medicinal use. DNA barcoding validated the species identity, enhancing its taxonomic classification. These findings highlight A. malabarica's potential for therapeutic applications and its importance in pharmacognostic standardization.

Microorganism-mediated arsenic reduction and its environmental effects

Arsenic (As) is a common toxic pollution element. The microorganism-mediated transformation of arsenic forms is an important part in the biogeochemical cycle of As. In the various microbial metabolic processes involving As, the coupling reduction of As has a great impact on the environment and is a process that is easily overlooked. From the biogeochemical cycle of As, this review introduces the microorganism-mediated methane oxidation, anaerobic ammonium oxidation, and iron (Fe)-sulfur (S) oxidation coupled with As reduction. Organic matter, pH, and redox potential are the main factors affecting the coupling reduction. After the coupling reduction, the toxicity and migration of As are greatly enhanced, which may increase the risk of As pollution. Therefore, it is of great significance to clarify the influences of carbon, nitrogen, Fe, S and other elements on the coupling process and explore more microbial processes coupled with As reduction for the prevention and control of As pollution.

Innovative Gravity-Fed Filtration System to Improve Coastal Community Water Quality

Efforts to meet clean water needs, especially for drinking water, depend on the condition of groundwater that is healthy and sufficiently available. Filtration is the process of separating particles from a liquid by passing the liquid through a permeable material. This study examines the Gravity-Fed Filtering System with innovative Imhoff technology, combined with a Primary Treatment stage, to produce clearer and higher-quality water. The objective of this research is to assess the effectiveness of this system in reducing contamination levels in groundwater, including iron (Fe), manganese (Mn), total hardness (Ca and Mg), and organic compounds. The study employed an experimental method with a quantitative approach and used a One Group Pretest-Posttest design. The research was conducted in two locations: Barombong Village in Makassar and Pauwo Village in Gorontalo. Fifteen samples were randomly selected for analysis. The study began with preliminary observations and initial testing in March 2022, followed by the main research and prototype evaluation in 2023-2024. The results show that the system effectively reduced Fe, Mn, organic compounds, and total hardness levels. In Makassar, the highest reduction in Fe is 87.3% in sample 8, while in Gorontalo, the highest reduction is 93.3% in sample 8. The highest reduction in manganese (Mn) in Makassar is 63.3% in sample 1, and in Gorontalo, it is 62.1% in sample 1. The highest reduction in organic compounds in Makassar is 81.6% in sample 3, while the lowest reduction in total hardness in Makassar is 77.1% in samples 4, 5, 6, and 10. In Gorontalo, the highest reduction in total hardness is 90.3% in samples 1, 2, and 3. Recommendations for the community, The use of gravity-fed filtering system technology as one of the media used to reduce iron and manganese concentrations is considered quite good, but for similar research to be carried out, modifications should be made to the media specifically starting with the size, shape and other variables that support it so that it is more effective in reducing pollutant concentrations.

Investigation of the Enrichment Coefficient for Cu, Fe, Mn and Ni Elements in Prunus armeniaca L. Plant, Hekimhan – Hasançelebi (Malatya)

Hasançelebi iron (Fe) deposit is located in Hekimhan district of Malatya province. Plants can take up the elements found in the soil they grow on and accumulate them in different organs. Such plants are effectively used in the exploration of mineral deposits and environmental pollution research. For this reason, Prunus armeniaca L. (apricot) plant (branch, leaf, fruit) and the soil samples on which this plant grew were taken from the study area and the enrichment coefficient (EC) of Cu, Fe, Mn and Ni elements were examined. The enrichment coefficient is

Probing Photo-Assisted Charge Storage Mechanism Using Bi-Fe Perovskite Oxide Electrode for Solar Supercapacitor.

In this study, the rhombohedral crystalline pure phase BiFeO3 (BFO) of irregularly shaped spherical particles of ≈100 nm and energy bandgap of ≈2.31 eV are synthesized by sol-gel auto-combustion method and explored as electrode material for photo-assisted supercapacitor. The electronic structure studies revealed that the coexistence of heterovalent Bi and Fe elements accelerated the electrochemical redox kinetics and photo-assisted charge storage properties. The resonant photoemission studies confirmed that near the Fermi level, the valence band spectra comprised the Fe3d and O2p hybridized states. The Fe-O hybridized state felicitates the charge transfer transitions (O2p (h+) + hυ ↔ Fe3+ + e- ↔ Fe2+), which assists the intercalation/de-intercalation process of OH- anions. Therefore, BFO has delivered 26.77% photo efficiency and the enhanced specific capacity of 21 Cg-1 at 2 Ag-1 in aq. 3m KOH under illumination, which is attributed to the accelerated photo-generated charge carrier separation and storage with surface polarization effect. BFO also delivered capacitance retention of 77.5% even after 1000 continuous GCD cycles under visible light irradiation.

PLASMA TRACE ELEMENTS IN MANAGED HUMBOLDT PENGUINS (SPHENISCUS HUMBOLDTI) FROM A SINGLE ZOOLOGICAL COLLECTION IN GERMANY.

Only limited data on concentrations of trace elements in the blood of avian species have been published. This information can play an important role in the conservation of endangered species and their protection from environmental pollutants and can also be clinically relevant in managed individuals. Some elements are essential for the health of the animals in human care, but little is known about expected concentrations for some of these elements. Therefore, 21 elements (silver, arsenic, gold, barium, cadmium, cobalt, chromium, copper, iron, iodine, mercury, magnesium, manganese, molybdenum, nickel, platinum, antimony, selenium, thallium, vanadium, and zinc) were measured by inductively coupled plasma mass spectrometry in lithium-heparinized plasma samples from Humboldt penguins (Spheniscus humboldti) from a single zoological collection in Germany (n = 39). The plasma concentrations of cadmium, nickel, platinum, antimony, and thallium were under the limit of detection in most of the analyzed samples. The results also showed that the females had significantly (P ≤ 0.05) higher concentrations of silver, barium, cobalt, chromium, iron, mercury, magnesium, vanadium, and zinc in their plasma in comparison with males. A correlation between the element plasma concentration and the age of the individuals could not be found. The differences in plasma concentrations of individual element between males and females could be due to hormonal influences on the metabolism. Further studies in different seasons and other age groups are needed in the future to investigate environmental and host effects in more detail and to understand physiological mechanisms responsible for observed differences.

Analysis of existent catalytic filter materials for removal of iron and manganese

Decentralized water supply in war and post-war times is one of the main sources of water for the population and enterprises. As a source of water supply, as a rule, water from wells is used for this type of water supply. The main problems of drill-fish water are the increased content of iron, manganese, hydrogen sulfide, hardness salts, nitrates, sulfates, chlorides in some regions, high dry residue. The rapid development of technologies based on membrane technologies such as reverse osmosis or nanofiltration allow us to adjust the salt composition of water, remove nitrates and make water suitable for drinking needs and production cycles. But before membrane technologies, compounds of iron, manganese, and hydrogen sulfide, which can form inorganic impurities on the surface of membrane elements and cause their premature failure, must be removed. One of the best methods of pre-treatment of water before membrane systems is complex ion-exchange materials, which are simultaneously capable of removing hardness salts, iron, and manganese. But the main disadvantage of such pre-filtration methods is the use of tableted salt, which makes this method expensive and not environmentally friendly. Purification of water from iron and manganese on pressure filters by catalytic loading with subsequent dosing of antiscalant before membrane installations is a modern trend in local water treatment. Catalytic loadings have been used for quite a long time, but most manufacturers do not provide clear and practical recommendations for their use. The use of such materials, as a rule, largely depends on many factors and is based on the experience of the specialist's qualifications. Analysis of the technical parameters of filter materials, analysis of parameters of the source water quality are the main components of the selection and organization of the correct technological scheme of water purification.

Electrochemical properties and hydrogen barrier properties of mixed sulphide-iron compounds

Sulphide-iron compounds are the corrosion product in hydrogen sulphide environment. When the surface of steel is covered by sulphide-iron compounds, the corrosion rate of steel becomes unpredictable. The effect on the corrosion resistance of sulphide-iron compounds layer is explored by controlling the proportion of single crystalline sulphide-iron compounds. In this study, single crystalline pyrite and pyrrhotite were synthesised through hydrothermal method. The pyrite and pyrrhotite were then mixed with ratios of 7:3, 1:1 and 3:7. The results revealed that ion selectivity was changed from cation to anion as the pyrrhotite content increased. What's more, the impedance value of the mixed sulphur iron compounds gradually decreased and the corrosion current density increased, which indicated that corrosion resistance reduced with the increasing of pyrrhotite content. As the pyrrhotite content increased, hydrogen permeation current and hydrogen content exhibited a gradual decrease, which showed an overall improvement in its hydrogen barrier properties.

CHERRY AND APPLE NUTRITION STATE IN THE ICDP MĂRĂCINENI, ARGEȘ EXPERIMENTAL FIELD AS INFLUENCED BY NEW FERTIGATION TECHNOLOGIES

Nutrition state of three apple varieties and Gisela cherry variety grafted on four parent stocks has been studied for a three years period, 2019-2021, through foliar analysis, in the frame of a project that aimed at early multi sensor diagnosis of nutritional stress in order to optimize fertigation methods in fruit tree growing. Leaves were collected to this end from every experimental lot in all three consecutive years; the samples were brought to the laboratory, dried and ground, and mineral nutrition elements (nitrogen, phosphorus, potassium, calcium, magnesium, zinc, copper, iron, and manganese) were analyzed, using dedicated laboratory methodology. The analytical results highlighted a normal nutrition of the fruit tree varieties, with differences (assessed by statistic computation) determined by variety/parent stock and applied treatments, all of them inside the normal contents ranges. The only exception consists of high manganese contents in cherry leaves which don’t necessarily endanger mineral nutrition.

Target Alloys of Iron-Based Materials through CALPHAD Method

The development of tailored alloys is an important aspect for enhancing efficiency across diverse applications in mechanical engineering. The use of computer-aided modelling offers an opportunity to enable a more efficient and targeted material development. In the present work, new iron-based alloys with specific properties were developed using the CALPHAD method. The alloy design developing process was carried out by using the simulation software JMatPro® and the data evaluation software EDA®. Using a full factorial plan, various alloys were modelled on the basis of the elements iron, nickel, vanadium, carbon, niobium and chromium. Afterwards, the alloys were narrowed down with regard to the criteria of carbide phase content, formability, and corrosion resistance. Subsequently, two final alloys were chosen based on their properties. Afterwards the selected final alloys were produced by mechanically blending different powder alloys and elements. These alloys were welded onto unalloyed steel using Plasma Transferred Arc welding and were characterised by using x-ray diffraction, scanning electron microscopy, hardness measurements, spark spectrometry and metallography. Subsequently, a verification of the welded samples regarding to chemical composition, phases, and corrosion resistance was carried out. The investigations showed that it was possible to simulate alloys with specific properties using computer-based software, which corresponded with the experimental studies.

Deciphering the atomistic mechanism underlying highly tunable piezoelectric properties in perovskite ferroelectrics via transition metal doping

Piezoelectricity, a fundamental property of perovskite ferroelectrics, endows the materials at the heart of electromechanical systems spanning from macro to micro/nano scales. Defect engineering strategies, particularly involving heterovalent trace impurities and derived vacancies, hold great potential for adjusting piezoelectric performance. Despite the prevalent use of defect engineering for modification, a comprehensive understanding of the specific features that positively impact material properties is still lacking, this knowledge gap impedes the advancement of a universally applicable defect selection and design strategy. In this work, we select perovskite KTa1−xNbxO3 single crystals with orthorhombic phase as the matrix and introduce Fe and Mn elements, which are commonly used in “hard” ferroelectrics as dopants. We investigate how transition-metal doping modifies piezoelectric properties from the perspective of intrinsic polarization behaviors. Interestingly, despite both being doped into the B-site as an acceptor, Mn doping enhances the local structural heterogeneity, greatly bolstering the piezoelectric coefficient beyond 1000 pC/N, whereas Fe doping tends to stabilize the polarization, leading to a substantial improvement in the mechanical quality factor up to 700. This work deciphers the diverse impacts of transition metal impurities on regulating polarization structures and modifying piezoelectric properties, providing a good paradigm for strategically designing perovskite ferroelectrics.