diff --git a/CITATION.cff b/CITATION.cff
index 6ecad8d..7b5f8e2 100644
--- a/CITATION.cff
+++ b/CITATION.cff
@@ -16,6 +16,9 @@ authors:
   - family-names: "Rao"
     given-names: "Akshay K."
     orcid: "https://orcid.org/0000-0002-9054-476X"
+  - family-names: "Dudchenko"
+    given-names: "Alexander V."
+    orcid: "https://orcid.org/0000-0002-4808-6195"
   - family-names: "Mauter"
     given-names: "Meagan S."
     orcid: "https://orcid.org/0000-0002-4932-890X"
diff --git a/docs/json_rep.rst b/docs/json_rep.rst
index f72d233..897eeaf 100644
--- a/docs/json_rep.rst
+++ b/docs/json_rep.rst
@@ -305,7 +305,7 @@ Below are two tables: first is all the ``Node`` subclasses and the second the at
     +---------------+--------------------+----------------------+---------------------------------+----------------------------------+-----------------------+-----------------------------+---------------------------+----------------------------+----------------------------+------------------------+----------------------------+----------------------------+----------------+-------------+--------------------------+-------------------------+-------------------------------+--------------------------+------------------+-----------+--------------------------+-----------------+---------+--------------+--------------+-----------------+---------+---------+--------------+-------------+----------------+
     | Reactor       | |check|            | |check|              | |check|                         | |check|                          |                       |                             | |check|                   |                            |                            | |check|                |                            |                            |                |             |                          |                         |                               |                          |                  |           |                          |                 |         | |check|      |              | |check|         | |check| |         |              |             |                |
     +---------------+--------------------+----------------------+---------------------------------+----------------------------------+-----------------------+-----------------------------+---------------------------+----------------------------+----------------------------+------------------------+----------------------------+----------------------------+----------------+-------------+--------------------------+-------------------------+-------------------------------+--------------------------+------------------+-----------+--------------------------+-----------------+---------+--------------+--------------+-----------------+---------+---------+--------------+-------------+----------------+
-    | StaticMixer   | |check|            | |check|              | |check|                         | |check|                          |                       |                             |                           | |check|                    | |check|                    |                        |                            |                            |                |             |                          |                         |                               |                          |                  |           |                          |                 |         | |check|      |              | |check|         | |check| |         |              |             |                |
+    | StaticMixing  | |check|            | |check|              | |check|                         | |check|                          |                       |                             |                           | |check|                    | |check|                    |                        |                            |                            |                |             |                          |                         |                               |                          |                  |           |                          |                 |         | |check|      |              | |check|         | |check| |         |              |             |                |
     +---------------+--------------------+----------------------+---------------------------------+----------------------------------+-----------------------+-----------------------------+---------------------------+----------------------------+----------------------------+------------------------+----------------------------+----------------------------+----------------+-------------+--------------------------+-------------------------+-------------------------------+--------------------------+------------------+-----------+--------------------------+-----------------+---------+--------------+--------------+-----------------+---------+---------+--------------+-------------+----------------+
     | Reservoir     | |check|            | |check|              | |check|                         | |check|                          |                       |                             | |check|                   |                            |                            | |check|                |                            |                            |                |             |                          |                         |                               |                          |                  |           |                          |                 |         |              |              |                 |         |         |              |             |                |
     +---------------+--------------------+----------------------+---------------------------------+----------------------------------+-----------------------+-----------------------------+---------------------------+----------------------------+----------------------------+------------------------+----------------------------+----------------------------+----------------+-------------+--------------------------+-------------------------+-------------------------------+--------------------------+------------------+-----------+--------------------------+-----------------+---------+--------------+--------------+-----------------+---------+---------+--------------+-------------+----------------+
diff --git a/pype_schema/connection.py b/pype_schema/connection.py
index 9660a0c..2cb1d1f 100644
--- a/pype_schema/connection.py
+++ b/pype_schema/connection.py
@@ -1097,6 +1097,7 @@ def __init__(
         contents,
         source,
         destination,
+        frequency=None,
         tags={},
         bidirectional=False,
         exit_point=None,
@@ -1106,6 +1107,7 @@ def __init__(
         self.contents = contents
         self.source = source
         self.destination = destination
+        self.frequency = frequency
         self.tags = tags
         self.bidirectional = bidirectional
         self.exit_point = exit_point
@@ -1122,10 +1124,15 @@ def __repr__(self):
         else:
             entry_point_id = self.entry_point.id
 
+        if self.frequency is None:
+            frequency_txt = "None"
+        else:
+            frequency_txt = str(self.frequency)
+
         return (
             f"<pype_schema.connection.Delivery id:{self.id} "
             f"contents:{self.contents} source:{self.source.id} "
-            f"destination:{self.destination.id} "
+            f"destination:{self.destination.id} frequency:{frequency_txt} "
             f"tags:{self.tags} bidirectional:{self.bidirectional} "
             f"exit_point:{exit_point_id} entry_point:{entry_point_id}>\n"
         )
diff --git a/pype_schema/data/desal_sample.json b/pype_schema/data/desal_sample.json
index 3b9a4dc..24fe3e7 100644
--- a/pype_schema/data/desal_sample.json
+++ b/pype_schema/data/desal_sample.json
@@ -175,7 +175,7 @@
         "tags": {}
     },
     "StaticMixer": {
-        "type": "StaticMixer",
+        "type": "StaticMixing",
         "elevation (meters)": null,
         "volume (cubic meters)": null,
         "input_contents": "ChlorinatedSeawater",
diff --git a/pype_schema/data/wrrf_sample.json b/pype_schema/data/wrrf_sample.json
index bb70c94..87b236f 100644
--- a/pype_schema/data/wrrf_sample.json
+++ b/pype_schema/data/wrrf_sample.json
@@ -254,7 +254,7 @@
     }
   },
   "OxygenPlant": {
-    "type": "Separator",
+    "type": "Separation",
     "input_contents": "Air",
     "output_contents": ["Oxygen", "IdealGas"],
     "num_units": 1,
diff --git a/pype_schema/node.py b/pype_schema/node.py
index 9bbf924..23c6e26 100644
--- a/pype_schema/node.py
+++ b/pype_schema/node.py
@@ -2071,14 +2071,14 @@ def del_dosing_rate(self):
     dosing_rate = property(get_dosing_rate, set_dosing_rate, del_dosing_rate)
 
 
-class StaticMixer(Reactor):
+class StaticMixing(Reactor):
     """A tank containing a static mixer,
     typically used for coagulation in water treatment.
 
     Parameters
     ----------
     id : str
-        StaticMixer ID
+        Static mixer ID
 
     input_contents : ContentsType or list of ContentsType
         Contents entering the mixer
@@ -2116,7 +2116,7 @@ class StaticMixer(Reactor):
     Attributes
     ----------
     id : str
-        StaticMixer ID
+        Static mixer ID
 
     input_contents : list of ContentsType
         Contents entering the mixer
@@ -2183,7 +2183,7 @@ def __init__(
 
     def __repr__(self):
         return (
-            f"<pype_schema.node.StaticMixer id:{self.id} "
+            f"<pype_schema.node.StaticMixing id:{self.id} "
             f"input_contents:{self.input_contents} num_units:{self.num_units}"
             f"output_contents:{self.output_contents} "
             f"dosing_rate:{self.dosing_rate} pH:{self.pH} "
@@ -4129,7 +4129,8 @@ def __eq__(self, other):
 
 
 class UVSystem(Disinfection):
-    """
+    """An ultraviolet light disinfection system.
+
     Parameters
     ----------
     id : str
@@ -4270,7 +4271,9 @@ def del_dosing_area(self):
 
 
 class Flaring(Node):
-    """
+    """The process of combusting biogas to convert the methane to carbon dioxide
+    before venting it to the atmosphere.
+
     Parameters
     ----------
     id : str
@@ -4348,7 +4351,7 @@ def __eq__(self, other):
         )
 
 
-class Separator(Node):
+class Separation(Node):
     """A class representing a separator that divides a mixture into its components,
     such as air separation units that produce high purity oxygen and nitrogen.
 
@@ -4451,7 +4454,7 @@ def __init__(
 
     def __repr__(self):
         return (
-            f"<pype_schema.node.Separator id:{self.id} "
+            f"<pype_schema.node.Separation id:{self.id} "
             f"input_contents:{self.input_contents} "
             f"output_contents:{self.output_contents} num_units:{self.num_units} "
             f"min_flow:{self.min_flow} max_flow:{self.max_flow} "
diff --git a/pype_schema/parse_json.py b/pype_schema/parse_json.py
index 243f38d..d28588c 100644
--- a/pype_schema/parse_json.py
+++ b/pype_schema/parse_json.py
@@ -447,7 +447,7 @@ def create_node(self, node_id, verbose=False):
         """
         if verbose:
             print("Creating node:", node_id)
-        (input_contents, output_contents) = self.parse_contents(node_id)
+        input_contents, output_contents = self.parse_contents(node_id)
         elevation = self.parse_unit_val_dict(self.config[node_id].get("elevation"))
         # strings like `elevation (meters)` and `volume (cubic meters)`
         # are included for backwards compatability
@@ -691,6 +691,8 @@ def efficiency_curve(arg):
                 )
                 electrical_efficiency = None
                 thermal_efficiency = self.config[node_id].get("thermal efficiency")
+                if thermal_efficiency is None:
+                    thermal_efficiency = self.config[node_id].get("thermal_efficiency")
 
             if electrical_efficiency:
 
@@ -887,12 +889,12 @@ def efficiency_curve(arg):
                 pH=pH,
                 tags={},
             )
-        elif self.config[node_id]["type"] == "StaticMixer":
+        elif self.config[node_id]["type"] == "StaticMixing":
             pH = self.config[node_id].get("pH")
             residence_time = self.parse_unit_val_dict(
                 self.config[node_id].get("residence_time")
             )
-            node_obj = node.StaticMixer(
+            node_obj = node.StaticMixing(
                 node_id,
                 input_contents,
                 output_contents,
@@ -933,11 +935,11 @@ def efficiency_curve(arg):
                 pressure_setting=pressure_setting,
                 tags={},
             )
-        elif self.config[node_id]["type"] == "Separator":
+        elif self.config[node_id]["type"] == "Separation":
             power_rating = self.parse_unit_val_dict(
                 self.config[node_id].get("power_rating")
             )
-            node_obj = node.Separator(
+            node_obj = node.Separation(
                 node_id,
                 input_contents,
                 output_contents,
@@ -1110,11 +1112,15 @@ def create_connection(self, connection_id, node_obj, verbose=False):
                 entry_point=entry_point,
             )
         elif self.config[connection_id]["type"] == "Delivery":
+            frequency = self.parse_unit_val_dict(
+                self.config[connection_id].get("frequency")
+            )
             connection_obj = connection.Delivery(
                 connection_id,
                 contents,
                 source,
                 destination,
+                frequency=frequency,
                 tags={},
                 bidirectional=bidirectional,
                 exit_point=exit_point,
@@ -2079,7 +2085,7 @@ def node_to_dict(node_obj):
                 node_dict["permeability"] = JSONParser.unit_val_to_dict(
                     node_obj.permeability
                 )
-        elif isinstance(node_obj, (node.Reactor, node.StaticMixer)):
+        elif isinstance(node_obj, (node.Reactor, node.StaticMixing)):
             if node_obj.volume is not None:
                 node_dict["volume"] = JSONParser.unit_val_to_dict(node_obj.volume)
 
@@ -2105,7 +2111,7 @@ def node_to_dict(node_obj):
                 node_obj, "flow_rate"
             )
             node_dict["num_units"] = node_obj.num_units
-        elif isinstance(node_obj, node.Separator):
+        elif isinstance(node_obj, node.Separation):
             if node_obj.volume is not None:
                 node_dict["volume"] = JSONParser.unit_val_to_dict(node_obj.volume)
             if node_obj.power_rating is not None:
diff --git a/pype_schema/tag.py b/pype_schema/tag.py
index 5d7bac3..4676779 100644
--- a/pype_schema/tag.py
+++ b/pype_schema/tag.py
@@ -11,7 +11,6 @@
 from .logbook import Logbook
 from .operations import Constant
 
-
 UNARY_OPS = ["noop", "delta", "<<", ">>", "~", "-"]
 BINARY_OPS = ["+", "-", "*", "/"]
 
diff --git a/pype_schema/tests/data/connection_less_than.json b/pype_schema/tests/data/connection_less_than.json
index 2412429..549dec7 100644
--- a/pype_schema/tests/data/connection_less_than.json
+++ b/pype_schema/tests/data/connection_less_than.json
@@ -295,7 +295,7 @@
       }
     },
     "OxygenPlant": {
-      "type": "Separator",
+      "type": "Separation",
       "input_contents": "Air",
       "output_contents": ["Oxygen", "IdealGas"],
       "num_units": 1,
@@ -1061,6 +1061,10 @@
             "avg": null,
             "units": "tons / day"
         },
+        "frequency": {
+          "value": "1",
+          "units": "day"
+        },
         "tags": {}
     },
     "SolidsDisposal": {
diff --git a/pype_schema/tests/data/merged.json b/pype_schema/tests/data/merged.json
index 3e1ab93..6c07bc5 100644
--- a/pype_schema/tests/data/merged.json
+++ b/pype_schema/tests/data/merged.json
@@ -1276,7 +1276,7 @@
         "num_units": 8
     },
     "OxygenPlant": {
-        "type": "Separator",
+        "type": "Separation",
         "input_contents": "Air",
         "output_contents": [
             "Oxygen", 
diff --git a/pype_schema/tests/data/merged_wwtp.json b/pype_schema/tests/data/merged_wwtp.json
index c66a038..32244ab 100644
--- a/pype_schema/tests/data/merged_wwtp.json
+++ b/pype_schema/tests/data/merged_wwtp.json
@@ -772,7 +772,7 @@
         "num_units": 8
     },
     "OxygenPlant": {
-        "type": "Separator",
+        "type": "Separation",
         "input_contents": "Air",
         "output_contents": [
             "Oxygen", 
diff --git a/pype_schema/tests/data/sample.pkl b/pype_schema/tests/data/sample.pkl
index b89c0d9..cafb664 100644
Binary files a/pype_schema/tests/data/sample.pkl and b/pype_schema/tests/data/sample.pkl differ
diff --git a/pype_schema/tests/test_connection.py b/pype_schema/tests/test_connection.py
index 436b961..299f729 100644
--- a/pype_schema/tests/test_connection.py
+++ b/pype_schema/tests/test_connection.py
@@ -370,7 +370,12 @@ def test_get_fallback_error(json_path, conn_id):
         (
             "../data/desal_sample.json",
             "AntiscalantDelivery",
-            "<pype_schema.connection.Delivery id:AntiscalantDelivery contents:ContentsType.Antiscalant source:ChemicalFactory destination:DesalPlant tags:{} bidirectional:False exit_point:None entry_point:None>\n",  # noqa: E501
+            "<pype_schema.connection.Delivery id:AntiscalantDelivery contents:ContentsType.Antiscalant source:ChemicalFactory destination:DesalPlant frequency:None tags:{} bidirectional:False exit_point:None entry_point:None>\n",  # noqa: E501
+        ),
+        (
+            "data/connection_less_than.json",
+            "BiosolidsDelivery",
+            "<pype_schema.connection.Delivery id:BiosolidsDelivery contents:ContentsType.WFBS source:ChemicalFactory destination:WWTP frequency:1 day tags:{} bidirectional:False exit_point:None entry_point:None>\n",  # noqa: E501
         ),
     ],
 )
diff --git a/pype_schema/units.py b/pype_schema/units.py
index 2bd69a8..da06845 100644
--- a/pype_schema/units.py
+++ b/pype_schema/units.py
@@ -133,7 +133,7 @@
 # default formatting includes 4 significant digits.
 # This can be overridden on a per-print basis with
 # print('{:.3f}'.format(3 * ureg.m / 9)).
-u.default_format = ".4g"
+u.default_format = ".4"
 
 units_path = os.path.join(os.path.dirname(__file__), "data", "unit_definitions.txt")
 u.load_definitions(units_path)